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					Tin deposits




                                                                                                                                           Exploration and Investment
in the Hodgkinson
Province
Current company exploration status
Higher tin prices are seeing a                                       Shortly	after	1985,	the	
                                                                     International Tin Council
                                                                                                         and Leichhardt, Nettle,
                                                                                                         Battle	and	Return	Creeks	
resurgence in exploration for tin                                    could no longer support
                                                                     this artificial price structure
                                                                                                         (Consolidated Tin Mines
                                                                                                         Ltd).	Lode	tin	exploration	
mineralisation in north Queensland.                                  despite the introduction of
                                                                     restricted production quotas
                                                                                                         is currently focused on the
                                                                                                         Cooktown Tinfield (Bluestone
This is due to its substitution for                                  for its country members. Tin        Tin	Ltd);	Herberton	Tinfield	
                                                                                                         (North Queensland Metals
                                                                     trading was de-listed from the
lead in solder, particularly the                                     London Metal Exchange and           Ltd	and	Kangaroo	Metals	Ltd);	
                                                                     the price plummeted sharply         Koorboora (Queensland Ores
environmentally friendly electronic                                  to	US$4000	per	tonne.	              Ltd);	Mount	Holmes	(Kangaroo	
                                                                                                         Metals	Ltd);	and	Mount	Garnet	
                                                                     The low tin price in the second
solder sector.                                                       half	of	1985	resulted	in	the	
                                                                                                         areas (Consolidated Tin Mines
                                                                                                         Ltd	and	Auzex	Resources	Ltd).	
                                                                     closure of many tin operations
                                                                     in north Queensland. During the
Current exploration is being     deposits in Queensland. The                                             Production and
                                                                     1980s	and	1990s,	the	market	
carried	out	at	Jeannie	River,	   level of historical production      for tin continued to suffer from    consumption
Kings Plains, Herberton Deep     from alluvial and eluvial tin                                           The top five tin producers
                                                                     falling demand and excess
Lead, and Leichhardt, Nettle,    mining from the Cooktown                                                are China, Indonesia, Peru,
                                                                     production. Extended periods of
Battle	and	Return	Creeks.	It	    and Herberton tinfields and at                                          Bolivia and Brazil, which in
                                                                     low prices resulted in extreme
is also being undertaken in      Mount Garnet has shown the                                              total	supply	more	than	90%	of	
                                                                     levels of retracted investment in
watercourses draining rocks      province to be one of leading                                           world production.
                                                                     tin exploration and mining until
of the O’Briens Creek and        tin producers in Australia.         the mid 2000s.                      The main demand for tin
Cooktown Supersuites and
                                 Before	the	1980s,	most	of	                                              comes from the electronics
proximal metasediments of                                            The	year	2004	marked	the	
                                 the tin production came from                                            industry, with approximately
the Hodgkinson Province.                                             beginning in a revival of
                                 alluvial and eluvial mining                                             45%	of	world	consumption	
                                                                     the tin price when it rose to
This article describes areas     of surface and near-surface                                             going into the production of
                                                                     US$8000	per	tonne,	attracting	
of exploration and historical    deposits. High tin prices                                               solders. The second largest
                                                                     many astute explorers back
alluvial, eluvial and lode tin                                                                           consumer	is	tinplate	(20%),	
                                 (US$8500	per	tonne	in	1981)	        to the Hodgkinson Province
mining operations. It shows                                                                              followed by the chemicals
                                 attracted many small alluvial       to take up strategic ground
that current exploration will                                                                            industry	(15%).	
                                 mine operators to work Tertiary     (Figure	1).	Current	exploration	
identify new resources and
                                 and Quaternary alluvial tin         for alluvial tin is being           The electronic solder sector
regenerate the tin mining
                                 deposits throughout north           carried	out	at	Jeannie	River	       is seen as an environmentally
industry in this region.
                                 Queensland. This practice           (Supersorb Environmental            friendly growth industry, with
The Hodgkinson Province          lasted	until	1985	due	to	a	floor	   NL);	Kings	Plains	(Australian	      tin replacing lead in lead-free
hosts the major significant      tin price that was propped up       Gold	Corporation	Pty	Ltd);	         solders. The growth in the
alluvial, eluvial and lode tin   by the International Tin Council.   and Herberton Deep Lead,            Asian electronic solder sector



                                                                                   Queensland Government Mining Journal Winter 2009 31
32 Queensland Government Mining Journal Winter 2009
and, in particular, the Chinese     major types being tin veins       are targeting potential tin       nature of the copper ore and




                                                                                                                                           Exploration and Investment
market has been driving             with associated base metals,      resources in the region.          the abrasive nature of the
demand for refined tin. These       tin greisens, tin skarns and                                        topaz-bearing ore.
                                                                      The collapse of tin prices
market developments alone           alluvial/eluvial deposits,
                                                                      in	1985	saw	the	end	              Current exploration for alluvial
resulted in an upward trend         including deep leads. The
                                                                      of production in north            tin is being carried out at
of increasing tin prices before     tinfields in the Hodgkinson
                                                                      Queensland until 1995,            Jeannie	River	(Supersorb	
2008.	After	the	closing	of	         Province are hosted by
                                                                      when Norminco Pty Ltd             Environmental	NL);	Kings	
several tin mines in Indonesia,     felsic, fractionated, S-and-I
                                                                      carried out alluvial/eluvial      Plains (Dianne Mining
world annual production of          type granites and associated
                                                                      mining at Leichhardt Creek,       Corporation);	and	Herberton	
tin	dropped	from	348	500	           acid volcanic rocks of
                                                                      near Mount Carbine. This          Deep Lead, and Leichhardt,
t	in	2005	to	333	000	t	in	          the O’Briens Creek and                                              Nettle,	Battle	and	Return	
2008,	creating	a	continuous	        Cooktown Supersuites.             operation used floating
                                                                                                        Creeks (Consolidated Tin
downward spiral of supply.          These granitoids intrude          dredges but encountered
                                                                                                        Mines	Ltd).
                                    lower Palaeozoic sediments of     production difficulties, and
Queensland deposits                 the Hodgkinson Formation.         closed	in	1997.	There	is	no	      The most recent lode tin
The Hodgkinson Province is                                            record of lode tin production     mining operation in the
known to contain significant        Production                        in	the	1980s.	Attempts	by	        Hodgkinson Province was
alluvial and lode tin resources     Currently there are few tin       small syndicates to mine          commissioned in late 2005 by
in the Cooktown and the             producing operations in the       the complex orebodies at          Bluestone Nominees Pty Ltd
Herberton tinfields. Deposit        Hodgkinson Province, but          Herberton failed due to low       (a	subsidiary	of	Metals	X	Ltd)	
styles are varied, with the         some exploration companies        tin prices, the arsenic-rich      at Collingwood. This operation
                                                                                                        was the largest tin producer
                                                                                                        in Australia at the time and
                                                                                                        produced	approximately	5700	
  Price history                     Consequently, during most         A major ‘tin crisis’ followed     t of tin concentrate a year at a
  From the 1930s, the tin cartel    of those 29 years, tin prices     and tin was de-listed from        grade	of	60%	Sn.	Underground	
  of 22 consumer and producer       rose sharply at times,            trading on the London Metal       mining was carried out at
  countries had attempted           especially in the period when     Exchange for about three          several levels but production
  informally to regulate tin        rampant inflation plagued         years. The International Tin      and labour shortages
  markets through purchasing        the world economy from            Council was dissolved soon        resulted in a temporary
  the resource as buffer stocks.    1973	through	to	1980.             afterward and the price of        halt	in	2008.	The	mine	is	
  These early arrangements                                            tin, now in a free-market         undergoing negotiation with
                                    The sharp recession of            environment, plummeted
  eventually led to the signing                                                                         Icon	Resources	Ltd	to	resume	
                                    1981–82	was	particularly	         sharply	to	US$4000	per	
  of the First International Tin                                                                        mining operation.
                                    harsh on the tin industry as      tonne	(/t).	
  Agreement	in	1956.	This	          well as most industrialised                                         Current lode tin exploration
  agreement was the first of a      countries, and tin                The first glimpse of a tin        is focused on the Cooktown
  series of agreements, all of      consumption declined              revival	was	in	2004,	when	        Tinfield	(Bluestone	Tin	Ltd);	
  which	collapsed	in	1985.	                                           the price broke through           Herberton Tinfield (North
                                    dramatically.
                                                                      US$10 000/t. In the ensuing       Queensland Metals Ltd
  Through these agreements,         The International Tin Council     years, the average price of       and	Kangaroo	Metals	Ltd);	
  the International Tin Council     tried to buffer steep declines    tin jumped in one year from       Koorboora (Queensland Ores
  was able to support the price     in prices through accelerated     about US$9000/t at mid            Ltd);	and	Mount	Holmes	
  of tin during periods of low      purchases for its stockpile.      2006	to	US$13	000/t	at	mid	       (Kangaroo	Metals	Ltd)	
  prices. It did this by buying                                       2007.	
                                    However, this activity                                              and Mount Garnet areas
  tin for its buffer stockpile
                                    required the International Tin                                      (Consolidated Tin Mines Ltd
  and was able to restrain the                                        The price of tin continued
                                    Council to borrow extensively                                       and	Auzex	Resources	Ltd).
  price during periods of high                                        its upward trend until
                                    from banks and metal              it reached a high of
  prices by selling tin from                                                                            Exploration
                                    trading firms to augment its      US$25	000/t	in	mid	2008.	
  the stockpile. This practice
                                    resources. The International      However, the unexpected
  was designed to assure                                                                                Alluvial tin deposits
                                    Tin Council continued to          economic downturn of
  a sufficient flow of tin to                                                                           Jeannie River – north of
                                    borrow	until	late	1985,	when	     the global financial crisis
  consumer countries and a                                                                              Cooktown
                                    it reached its credit limit.      suppressed tin prices back
  justifiable profit for producer                                                                       The	Jeannie	River	group	of	
                                    The artificially inflated floor   to	2004	levels	in	early	2009.	
  countries.                                                                                            prospects, which includes
                                    prices at the London Metal        Recent	improvement	in	            the Discovery Gossan, Leet
  During the 29 years of the tin    Exchange could not support        commodity prices witness          and Sheehan zones, is
  agreements, it was apparent       the International Tin Council     a steady recovery of world        95 km north-west of
  that the buffer stockpile was     and its members, despite          market confidence in tin          Cooktown. Carpentaria
  ineffective for defending         the production quota that         has improved its value to         Exploration Company Pty Ltd
  the artificial ceiling prices.    was in place.                     US$16	000/t	in	mid	2009.          discovered	the	Jeannie	River	
                                                                                                        deposit	in	1979	from	stream	


                                                                                    Queensland Government Mining Journal Winter 2009 33
Current                           been hindered by continued
                                  negotiation of land access
                                                                    the area for its rare-earth
                                                                    minerals potential without
                                                                                                       higher grade area to define an
                                                                                                       economic resource. No further
exploration for                   agreements and procurement
                                  of exploration funding.
                                                                    much success. The area was
                                                                    taken	up	as	EPM	15616	by	
                                                                                                       work was carried out after the
                                                                                                       tin	price	collapsed	in	1985.	
alluvial tin is                   Since then little on ground
                                  exploration was carried out,
                                                                    Dianne Mining Corporation
                                                                    in	late	2007.	The	tenement	
                                                                                                       Ravenshoe	Tin	Dredging	
                                                                                                       Company Ltd applied for
being carried out                 and in 2009, Independence
                                  Group NL entered a joint
                                                                    was subsequently assigned to
                                                                    Australian Gold Corporation
                                                                                                       a mining lease to hold the
                                                                                                       high-grade alluvial area.
at Jeannie River;                 venture agreement to explore
                                  the	Jeannie	River	tenement.
                                                                    Pty	Ltd	in	2008.
                                                                                                       Revaluation	of	all	the	
                                                                    The China Camp prospect is
Kings Plains;                     Kings Plains and China Camp –     56	km	south	of	Cooktown.	In	
                                                                                                       data	in	1994	led	to	the	
                                                                                                       identification of richer zones
                                  Cooktown Tinfield                 the	1980s,	Southern	Venture	
and Herberton                     The Kings Plains prospect is      NL explored the Permian
                                                                                                       with a measured and inferred
                                                                                                       resource	of	1.18	million	bcm	
                                  25 km south-west of Cooktown      Roaring	Meg	Adamellite,	
Deep Lead, and                    and has been explored for         which intrudes sediments of
                                                                                                       grading	573	g/bcm	Sn	at	an	
                                                                                                       average	depth	of	18	m	(Tin	
                                  deep lead alluvial cassiterite    the Hodgkinson Formation.
Leichhardt,                       along the ancestral Annan         Alluvial cassiterite has been
                                                                                                       Australia	NL	prospectus).	
                                                                    shed from the contact of the       Further drilling was carried
                                  River	valley	to	depths	below	
Nettle, Battle                    30.5	m.	In	the	eastern	end	of	    adamellite and the sediments       out on the North Terrace
                                                                    into	Baird	Creek,	Roaring	         and South Terrace alluvial
                                  the prospect, the cassiterite
and Return                        grade was found to be higher      Meg Creek and an older fossil      areas on either side of the
                                                                    drainage system.                   Leichhardt Creek channel
                                  and the cassiterite coarser
Creeks.                           than other parts of               Cultus Gold NL bought into
                                                                                                       within the mining lease. This
                                                                                                       work upgraded the deposit to
                                  the prospect.                     the Baird Creek project in         a measured resource of
                                  In	1980,	Triako	Mines	NL,	        he	first	half	of	1985	and	         1.3	million	bcm	at	a	grade	of	
sediment sampling in which        Serem Australia Ltd and Buka      production was scheduled for       420	g/bcm	Sn.
two major tin anomalies were      Minerals NL investigated the      later that year. However, Baird
characterised by creeks with                                        Creek was placed                   In	1994,	Norminco	Pty	Ltd	
                                  potential of the Kings Plains
sediments	assaying	0.14	to	                                         on a care and maintenance          acquired the Leichhardt
                                  deposit for a dredging or
1.1%	Sn.	                                                           basis	in	1987	due	to	the	          Creek project and started
                                  gravel pumping operation.
                                                                    prevailing tin price. The leases   alluvial mining on the
Follow-up exploration of          Drilling indicated the presence
                                                                    expired in the 1990s and no        North Terrace using a
the Sheehan and Discovery         of two mineralised wash
                                                                    further exploration was carried    1.5 million bcm/annum
Gossan lode systems               zones separated by a very low
                                                                    out. China Camp is now             alluvial floating concentrator
indicated abundant pyrrhotite     grade	zone.	Resources	were	
                                                                    within the Wet Tropics World       fed by a land-based
with tin, copper, arsenic, lead   calculated as an indicated
                                                                    Heritage Area.                     excavator. When mining
and zinc mineralisation similar   27.55	Mm3 of alluvium at
                                                                                                       ceased	in	1997,	94	t	of	tin	
to complex sulphide lodes         230	g/m3 cassiterite. The         Leichhardt Creek – Mount           metal had been produced at
in the Herberton Tinfield.        best grade intersected was        Carbine                            an exceptionally high grade
Metallurgical testing indicated   10	m	of	wash	at	267	g/m3          The Leichhardt Creek tin mine is   of	76%	Sn.	Norminco	Pty	Ltd	
potential	recoveries	of	69%	      cassiterite. The alluvium         12 km east-south-east of Mount     later experienced financial
of the cassiterite. Forty-one     deepens to the west, with         Carbine. The creek drains the      difficulties.
percussion	holes	(3662	m,	        an accompanying lowering          western side of Mount Lewis,
including 11 holes at Saddle      in grade. A test plant was        which contains numerous            Tin Australia NL took over
Hill)	and	17	diamond	core	        used to treat bulk samples.       cassiterite-bearing and            the project in 1999 and
holes	(5263	m)	were	drilled	up	   Gravity, electromagnetic          wolframite-bearing quartz and      suggested that future work
until	the	end	of	1984,	giving	    (EM)	and	resistivity	methods	     quartz greisen veinlets within     should include a feasibility
indicative	resources	of	6.7	Mt	   were used to delineate the        the Mount Carbine Granite.         study encompassing not just
of mineralisation at a grade of   ancestral channel of the          Minor amounts of wolframite        the Maryfarms dredge path
0.8%	Sn.	Low	tin	prices	          Annan	River;	gravity	was	found	   occur in the alluvium.             but also the proposed ‘Four
precluded following up            to provide the best definition.                                      Creeks’ dredge path. The
                                                                    Ravenshoe	Tin	Dredging	
the deposit.                      A feasibility study showed                                           entire known resource could
                                                                    Company Ltd undertook
                                  that this large, low-grade                                           be mined in the first full year
Supersorb Environmental                                             drilling	in	the	1960s	and	
                                  deposit was not viable at the                                        of operation.
NL acquired the project                                             1970s	in	the	Maryfarms	
                                  prevailing tin prices.
(EPM	14580)	from	Friends	                                           area.	A	46	million	bank	           The Leichhardt Creek deposit
Exploration	Pty	Ltd	in	2006.	     Tin Creek Mining Corporation      cubic	metres	(bcm)	dredging	       was explored by Consolidated
Stream sediment sampling          Ltd purchased the prospect        prospect	grading	185	g/            Tin	Mines	Ltd	(EPM	14579)	in	
and geological mapping was        from Serem Australia Ltd          bcm Sn was identified in           2008,	the	company	quoted	an	
planned	for	the	2007	field	       in	1984.	In	1988,	Astrick	        1973.	In	late	1985,	drilling	      indicated	resource	of	1.3	million	
season but exploration has        Resources	NL	briefly	assessed	    was completed within the           bcm	at	393	g/bcm	Sn.


34 Queensland Government Mining Journal Winter 2009
Herberton Deep Lead –              Battle Creek, Nettle Creek and    The ground was harder at           operations, sold equipment




                                                                                                                                          Exploration and Investment
Herberton Tinfield                 Return Creek – Mount Garnet       depth, and this limited the        and started to surrender
Tin was first discovered in        Ravenshoe	Tin	Dredging	           depth of drill testing.            tenements.
Herberton	in	1880	when	a	          Company Ltd carried
                                                                     From	1965	to	1982,	the	            Norminco Pty Ltd purchased
number of very high-grade          out dredging operations
                                                                     Ravenshoe	Tin	Dredging	            the remaining Oakbridge
tin lodes were found in the        in Battle Creek, near
                                                                     Company Ltd dredged Nettle         Ltd	alluvial	projects	in	1994.	
surrounding hills. Cemented        Mount	Garnet,	from	1957	
                                                                     Creek	and	produced	6725	t	         Norminco Pty Ltd was acquired
alluvial cassiterite-bearing       to	1965	for	a	recorded	
                                                                     of cassiterite concentrate         by Mount Carrington Mines
wash passing under basalt          production	of	about	14	
                                                                     from	30.7	million	bcm	at	an	       Ltd later that year. In 1999,
on the southern edge of the        million	bcm	for	4104	t	of	
                                                                     average	grade	of	153	g/bcm	        Tin Australia NL took over
hills was mined. Wash under        tin	concentrate	(~29	g/bcm	
                                                                     cassiterite. The dredge started    ownership of the area but
the basalt in the ancestral        cassiterite	concentrate).	
                                                                     from upstream and continued        did not carry out any work on
Wild	River,	5	km	south	of	         The Battle Creek deposit
                                                                     southwards downstream.             the projects.
Herberton, became known            was	re-evaluated	in	1984.	
                                                                     Its path took it across the
as the Herberton Deep Lead,        It was estimated that the                                            Consolidated Tin Mines Ltd
                                                                     Kennedy Highway at the
which extends from Herberton       high-grade altered granite-                                          purchased the Nettle Creek
                                                                     small settlement of Innot
to Prairie Creek and south for     greisen contained                                                    prospect	in	2007	and	hopes	to	
                                                                     Hot Springs.
a	further	26	km	to	the	junction	   472	000	bcm	grading	                                                 commence a mining operation
of the Millstream and the          1080	g/bcm	cassiterite	           In	1981,	Oakbridge	Ltd	            at	Nettle,	Battle	and	Return	
Wild	River.	                       (~617	000	m3	grading	~            bought the Nanyetta lease          Creeks in 2009.
                                   1270	g/m3 cassiterite             from Southland Mining Ltd
The Herberton Deep Lead            concentrate)	extending	to	        (a subsidiary of Tableland Tin     Lode tin deposits
was mined from tunnels             approximately	48	m	below	         Dredging	Ltd),	which	reported	     Cooktown Tinfield
driven under the basalt from       the	surface.	In	1985,	an	         two years of high-grade tin        The Cooktown Tinfield in
the banks of the current           aircore drilling program          mining remained. Because           the	Rossville	area	hosts	
Wild	River.	About	4000	t	of	       was completed to test             of falling tin prices, dredging    sheeted-veins	(Mount	Amos)	
cassiterite concentrate was        deeper sections of the            on the lease was suspended         and greisens veins/greisen
won from the deep lead;            altered granite and gave          in	1981,	after	the	production	     alteration	(Collingwood).	The	
the wash was very rich with        a	resource	of	683	000	            of	142	t	tin	concentrates.	        most prospective areas for
coarse-grained cassiterite and     bcm	grading	838	g/bcm	            Oakbridge Ltd continued            hard rock greisen deposits
contained minor ilmenite,          cassiterite concentrate to        exploration	at	Robertson’s	        are in the roof zones of S-type
wolframite, topaz, gold and        depths	of	68	m	below	surface.	    Creek and Smith’s Creek in         granites of the Cooktown
rare diamonds. Old tunnels                                           the Mount Garnet area. At the      Supersuite capped by the
were	entered	in	the	1960s	and	     Norminco Pty Ltd purchased
                                                                     time, Oakbridge Ltd was the        Hodgkinson Formation.
high-grade tin assays of wash      the Battle Creek and Nettle
                                                                     largest alluvial tin producer
were obtained. Production          Creek deposits in 1995. They                                         The Collingwood tin deposit is
                                                                     in Australia and expected
from	1983	to	1988	was	~            were subsequently offered to                                         35	km	south	of	Cooktown	and	
                                                                     a recovery in tin prices and
11.4	t	cassiterite	concentrate.	   Tin Australia NL and then to                                         the mine is on Collingwood
                                                                     demand	in	1982.
The Bradlaugh and Cassowary        Consolidated Tin Mines Ltd.                                          Hill, near the crest of a ridge
Creek deep leads are thought                                         After the introduction of          connecting Mount Walker and
                                   The Nettle Creek deep lead,
                                                                     production	quotas	in	1982,	        Mount	Tolbert.	Recent	company	
to be tributaries of the main      10 km east of Mount Garnet,
                                                                     Oakbridge Ltd was forced to        exploration reported that the
deep lead.                         was	discovered	in	1881	and	
                                                                     shutdown the two dredges—          Collingwood mineralisation
In	the	1980s,	Mount	Arthur	        was worked intermittently
                                                                     Ravenshoe	Tin	Dredging	            is greisen style with steep
                                   over	50	years.	From	1931	to	
Molybdenum NL mined                                                  Company Ltd on Nettle Creek        siliceous sheeted veins,
                                   1946,	Nettle	Creek	Company	
alluvial tin from Cassowary                                          in	1982	and	Tableland	Tin	         albitic veins and flat-lying
                                   and The Broken Hill Pty
Creek but, due to the quota                                          Dredging	Ltd	on	Return	Creek	      greisen within granites of
                                   Company Ltd sluiced the
system at the time, was                                              in	1984—and	re-examine	            the Collingwood Granite. The
                                   area	and	produced	~400	t	
unable to carry on balancing                                         high-grade areas.                  flat-lying veins were mined
                                   of cassiterite concentrate.
mining operation costs and                                                                              by sluicing in the 1900s.
                                   Alluvial Gold Ltd investigated    Oakbridge Ltd reviewed its
ceased	operations	in	1985.	                                                                             Mineralisation occurs as a
                                   the	deep	zone	in	Return	Creek	    alluvial mining operations in
The company continued                                                                                   series of closely spaced,
                                   in	1970	and	interpreted	          1984	but	failed	to	find	a	joint	
to hold an interest in the                                                                              subparallel, siliceous-sheeted
                                   the deposit as a ‘kaolinised      venture partner to continue its
Cassowary Creek deposit in                                                                              greisen lodes that trend north-
                                   lode’ that had been buried        projects. Open-hole drilling
the 1990s.                                                                                              south and dip steeply east.
                                   by the Battle Creek channel       confirmed the presence of
                                                                                                        Cassiterite occurs as granular,
Consolidated Tin Mines Ltd         sediments. Continued drilling     unmined high-grade wash.
                                                                                                        sub-spherical grains between
currently holds the deposit        in	the	mid	1970s	confirmed	       Depths to the deep lead
                                                                                                        0.5 mm and 2 mm in diameter
under	EPM	14185	and	intends	       the kaolinised nature and         ranged	from	14	to	20	m.	The	
                                                                                                        within the lodes.
to conduct systematic drill        interpreted the rock type as a    company continued with
evaluation of the deep lead,       greisen zone that is quite soft   limited tin production until       From	1962	to	1967,	The	
followed by mining.                and clayey closer to surface.     1989,	after	which	it	closed	its	   Broken Hill Pty Company Ltd


                                                                                   Queensland Government Mining Journal Winter 2009 35
Collingwood underground lode
                                                                                                    tin	metal	production	of	282	
showing rounded to subrounded                                                                       t (Bluestone Tin Ltd Annual
cassiterite in greisen                                                                              Report,	2006).	Tin	concentrate	
                                                                                                    was shipped to Malaysia for
                                                                                                    refining and smelting, and
                                                                                                    sold on the Kuala Lumpur
                                                                                                    metal exchange.
                                                                                                    The reserves estimate as at
                                                                                                    30	June	2006	was	953	900	t	
                                                                                                    at	1.19%	Sn	within	a	larger	
                                                                                                    resource	base	of	1	280	900	t	
                                                                                                    at	1.27%	Sn.	Most	of	the	ore	
                                                                                                    came from the north-north-
                                                                                                    west trending Amos lode along
                                                                                                    a strike length exceeding
                                                                                                    1.5	km	and	up	to	3	m	wide.	
                                                                                                    Exploration outlined four,
                                                                                                    smaller, subparallel lodes.
                                                                                                    The average ore grade was
                                                                                                    1.3%	cassiterite,	with	grains	
                                                                                                    up	to	3	mm	in	size	occurring	
                                                                                                    in greisen hanging wall. The
The most                           Collingwood tin
                                   treatment plant                                                  orebody dips steeply to the
                                                                                                    east.	In	2008,	the	company	
prospective                                                                                         stated that the mine had not
                                                                                                    achieved planned grades and
areas for hard                                                                                      metal production as a result
                                                                                                    of failure to attract skilled
rock greisen                                                                                        miners. Underground mining
                                                                                                    was halted in early May and
deposits are in                                                                                     milling completed in late
                                                                                                    May	2008.	
the roof zones of
                                                                                                    In	May	2009,	Icon	Resources	
S-type granites                                                                                     Ltd reported ongoing
                                                                                                    negotiation to acquire the
of the Cooktown                   that the deposit had a           and maintenance, pending an      mine from Metals X Ltd and
                                  geological	resource	of	4	        improvement in tin prices.       had plans to resume mining.
Supersuite                        Mt	at	0.7%	Sn,	with	minor	                                        Herberton Tinfield
                                                                   Acacia Metals Pty Ltd
                                  copper and silver contents.                                       The Herberton Tinfield, located
capped by the                     It was estimated that the
                                                                   and North Ltd acquired
                                                                                                    between Almaden, Dimbulah,
                                                                   Collingwood from Shell
                                  central, higher-grade orebody                                     Mount Garnet and Herberton,
Hodgkinson                        could contain a probable
                                                                   Company of Australia Ltd
                                                                                                    is one of the most intensely
                                                                   in	1995.	Amalg	Resources	
                                  ore	reserve	of	750	000	t	at	                                      mineralised areas of the state.
Formation.                        1.69%	Sn.	An	underground	
                                                                   NL obtained an option over
                                                                                                    Tin occurs in several highly
                                                                   the Collinwood project in
                                  drive was excavated into                                          mineralised centres, including
                                                                   March	1997.	Anglo	Gold	
                                  the	ore	zone	in	1987	and	                                         Herberton, Irvinebank,
mapped and sampled the                                             Australia Metals Pty Ltd took
                                  a short vertical raise was                                        Watsonville, Emuford,
Collingwood mine area. In                                          over the project in 2000
                                  completed. A pre-feasibility                                      Stannary Hills, Brownville,
1972,	Carpentaria	Exploration	                                     and transferred the title to
                                  technical and economic study                                      Coolgarra and Silver Valley.
Company Pty Ltd carried out                                        Bluestone Nominees Pty Ltd in
                                  also	commenced	in	1987.	                                          Local mineral zonation in
a regional stream sediment                                         the same year.
                                  The company was granted                                           the Herberton area is very
sampling and confirmed an
                                  six mining leases in the         Bluestone Nominees Pty Ltd       complex and the generalised
anomalous zone with up to
                                  immediate	area	in	1989	and	      (a wholly-owned subsidiary of    zonation away from the source
400	ppm	Sn	in	hornfelsed	
                                  two mineral development          Metals	X	Limited)	commenced	     of mineralisation is tungsten,
sediments west of the
                                  licences in 1991. Shell          underground mining in late       molybdenum, bismuth, tin,
historical Collingwood lode
                                  Company of Australia Ltd         2005 and the first concentrate   copper, lead and silver. Most
mine.
                                  reported an indicated resource   was shipped in February          of the Herberton Tinfield
In	1987,	Shell	Company	of	        of	2.2	Mt	at	1%	Sn.	The	         2006.	The	mine	processed	        mineralisation forms adjacent
Australia Ltd announced           project was placed on care       45	376	t	of	ore	for	a	total	     to greisenised, porphyritic


36 Queensland Government Mining Journal Winter 2009
microgranite sills intruding                                                                                                                     tourmaline. Tin mineralisation,




                                                                                                                                                                                                                             Exploration and Investment
                                    Headframe of the
the Hodgkinson Formation.           Vulcan mine                                                                                                  of	which	approximately	80%	
Significant quantities of copper                                                                                                                 is present as cassiterite and
ore were mined from the Silver                                                                                                                   20%	as	stannite,	occurs	in	
Valley area. The Great Northern                                                                                                                  faults, fractures and joints.
Mining Company detected
                                                                                                                                                 Tin has been the focus of the
subeconomic concentrations of
                                                                                                                                                 Baal Gammon area dating
indium in the silver-lead ores.
                                                                                                                                                 back	to	the	1930s	when	the	
The Vulcan tin mine is 1 km                                                                                                                      United Northern Australian
south-west of Irvinebank                                                                                                                         battery operated at the site.
and was one of the richest                                                                                                                       From	1979	to	1985,	Great	
tin mines in this area. It                                                                                                                       Northern Mining Corporation
produced	~180	000	t	at	                                                                                                                          NL entered into a number of
around	5%	cassiterite	                                                                                                                           exploration joint ventures
concentrates to a depth of                                                                                                                       with a consortium managed
~500	m	between	1888	and	                                                                                                                         by Newmont Holdings Pty
1930.	The	deposit	was	a	                                                                                                                         Ltd. During this period, the
near-vertical pipe-like body.                                                                                                                    main exploration focus was
Mineralisation occurs                                                                                                                            the United Northern Australia
in greenish chloritised rock                                                                                                                     or UNA area (now referred to




                                                                                                       Courtesy of North Queensland Metals Ltd
that weathers to a rusty red                                                                                                                     as	Baal	Gammon).	Newmont	
on the surface.                                                                                                                                  Holdings Pty Ltd reported a
                                                                                                                                                 resource	of	1.3	Mt	at	
In	1977,	the	property	                                                                                                                           1.24%	Cu,	0.31%	Sn	and	
was reviewed by Barrier                                                                                                                          45.8	g	/t	Ag.	An	additional	
Exploration NL, which                                                                                                                            1.2	Mt	at	0.31%	Cu	and	
concluded there were three                                                                                                                       0.18%	Sn	could	have	been	
exploration targets. One
was the depth extension of          Drilling at Baal Gammon
the pipe and the other two
were surface geochemical
prospects based on coincident
tin and copper anomalies. In
1983,	Great	Northern	Mining	
Corporation NL acquired the
operations of Loloma Ltd,
including its Jumna mill near
Irvinebank. The Herberton
mill	closed	in	December	1983	
and	the	Jumna	mill	in	1989.	
During this period, Great
Northern Mining Corporation
NL entered into a number of
exploration joint ventures with
                                                                                                                                                                                   Courtesy of North Queensland Metals Ltd



other companies. The most
significant was a consortium
managed by Newmont
Holdings	Pty	Ltd	from	1979	to	
1985.	Great	Northern	Mining	
Corporation NL mined ore from
the joint venture and other
areas and continued to test tin
prospects	until	1989.	             exploration tenement EPM        a granitic intrusion. The                                                     mined with the overlying
                                   14741	to	North	Queensland	      sequence is intruded by a                                                     waste in the planned pit area.
There was little exploration       Metals Ltd in 2005.                                                                                           Metallurgical testing indicated
                                                                   porphyry	sill	(the	UNA	Sill)	
activity in the 1990s and
                                                                   that is a greisenised quartz-                                                 that	a	recovery	rate	of	24%	
title to the areas of interest     The Baal Gammon deposit is
                                                                   sericite-topaz-muscovite rock.                                                would be achieved.
was held by other parties. In      6.4	km	west	of	Herberton	and	
2004,	Walker	Resources	Pty	        is hosted by a roof pendant     The orebody is adjacent to a                                                  However, Newmont Holdings
Ltd took over the Vulcan mine      of Hodgkinson Formation         stanniferous, quartz porphyry                                                 Pty Ltd, ICI Australia Ltd
and sold the mining lease and      sedimentary rocks within        intrusive that is locally rich in                                             and	HC	Sleigh	Resources	


                                                                                  Queensland Government Mining Journal Winter 2009 37
Ltd withdrew from the joint
venture	in	1985	as	the	size	
                                   The Mount                        expired in 1999. Tin Australia
                                                                    NL carried out minor field work
                                                                                                      associated with greisen zones
                                                                                                      in the Hodgkinson Formation.
and grade of the reserves were
considered uneconomical for a
                                   Holmes area has                  and assessments of the larger
                                                                    known deposits. Following the
                                                                                                      Koorboora-Sunnymount area
                                                                                                      The Sunnymount area includes
large-scale mining operation.
                                   been a sporadic                  withdrawal of Tin Australia NL,
                                                                    Worldwide	Gold	Resources	
                                                                                                      the mines and workings
Great Northern Mining                                                                                 of Tommy Burns, Cabbage
Corporation NL continued to        producer of tin                  International Ltd undertook an
                                                                    extensive data review. Various
                                                                                                      Patch, O’Shea’s Prospect,
develop and exploit known                                                                             New Year’s Gift, Kerosene Tin,
tin deposits in the area           and tungsten                     groups have expressed
                                                                    interest in these tenements
                                                                                                      Prince Alfred, Christmas Gift,
using Walkerminco Pty Ltd’s                                                                           Cyclone, King of the Hills,
database. The company              since 1894,                      since 1999 and several
                                                                    research and assessment
                                                                                                      Queen of the Hills and others.
reported a large stockwork                                                                            Workings are scattered over
system containing tin, silver      when alluvial                    studies were undertaken by
                                                                    Arkaroola	Resources	Pty	Ltd.	
                                                                                                      an	8	km	by	4	km	area.	The	
and copper mineralisation                                                                             Tommy Burns mine produced
at Baal Gammon with an             cassiterite was                  The Sailor tin prospect is        more	than	4300	t	cassiterite	
indicated	reserve	of	3	Mt	at	                                       currently being explored by       and wolframite concentrate up
1.2%	Cu,	46	g/t	Ag	0.3%	Sn	        discovered.                      North Queensland Metals Ltd       to	1984,	by	open	stoping	from	
and 50 g/t In.                                                      under	EPM	14742.                  decline access, at an average
                                   Mineralisation                   Mount Holmes                      grade	of	1.6%	combined	
In	2006,	North	Queensland	
                                                                                                      metal. This deposit consists
Metals Ltd commenced a             comprises                        The Mount Holmes area has
                                                                    been a sporadic producer of       of steeply dipping, tin and
feasibility study to re-evaluate
                                                                                                      tungsten-bearing, lensoidal,
the Baal Gammon deposit. A         swarms of                        tin	and	tungsten	since	1894,	
                                                                    when alluvial cassiterite was     pipe-like bodies cutting
Joint	Ore	Reserves	Committee	
                                                                                                      across micro-quartzite,
(JORC)	compliant	resource	         quartz-feldspar                  discovered. Mineralisation
                                                                    comprises swarms of quartz-       micaceous siltstones and
estimate was calculated and
                                                                                                      siliceous siltstones.
baseline environmental studies     and pegmatite                    feldspar and pegmatite veinlets
                                                                    containing coarse-grained
and preliminary evaluation work                                                                       The mine was operated by
commenced. Drilling results        veinlets                         cassiterite and wolframite. The
                                                                    veins are similar to those at
                                                                                                      Gold Copper Exploration NL
announced	in	2007	included	                                                                           up	until	the	mid	1980s.	
4.05	m	at	8.5%	Cu,	1.18%	Sn,	      containing                       Mount Carbine.                    The company reported a
224	g/t	Ag	and	642	g/t	In	from	                                     Between	1983	and	1985,	           resource	of	60	000	t	at	
36.85	m,	7.4	m	at	3.36%	Cu,	       coarse-grained                   S.R.	Ribich	mined	eluvial	        0.62%	cassiterite.	The	
1.24%	Sn,	97	g/t	Ag	and	                                            material from the top of the      Sunnymount operation was
264	g/t	In	from	39	m,	and	         cassiterite and                  mountain and produced             closed	in	1984	because	the	
5	m	at	5.16%	Cu,	0.21%	Sn,	                                         approximately	13	t	of	            company’s	quota	of	80	tpa	
128	g/t	Ag	and	337	g/t	In	         wolframite.                      cassiterite concentrates.         was not sufficient to maintain
from	33	m.	In	2008,	North	                                          In	1986,	Houston	Oil	             profitability, even though the
Queensland Metals Ltd reported                                      and Minerals Australia            mine had been the company’s
                                   of the Hodgkinson Formation.
probable	ore	reserve	of	3.3	Mt	                                     Incorporated explored             principal income source for
                                   Tin occurs as cassiterite,
at	grade	of	0.93%	Cu,	0.2%	Sn,	                                     alluvium along Little Plum Tree   the previous 10 years. A
                                   in association with minor
32.04	g/t	Ag	and	29.31	g/t	In.	                                     Creek, which drains the Mount     reassessment of the prospect
                                   concentrations of sulphide
The mine is expected to process                                     Holmes area. They estimated       increased the resource to
                                   minerals and fluorite, within
500 000 t over a seven year                                         a	volume	of	around	48	000	m3      92	900	t	at	1.04%	cassiterite	
                                   subhorizontal lenticular
mine	life	to	produce	~20	000	t	                                     grading	400	g/m3 cassiterite in   and	0.41%	wolframite.	
                                   greisen bodies.
of Cu-Sn-Ag-In concentrate per                                      the upper regions of the creek    The Sunnymount mill was
year.	In	2008,	North	Queensland	   The Sailor prospect has          system.	In	1989,	Poseidon	        refurbished and a carbon
Metals Ltd also acquired EPM       had significant exploration      Exploration	Ltd	(EPM	5968)	       circuit added to treat gold ore
14016	to	conduct	further	          under mining lease tenure.       carried out rock chip sampling;   in	1987.	No	exploration	for	tin	
exploration for satellite ore      Queensland Polymetallic          a	resource	of	7–10	Mt	grading	    and tungsten was carried out
resources to supplement the        Resources	Pty	Ltd	was	granted	   0.055%	Sn	and	0.01%	WO3	          in	the	area	between	1985	and	
Baal Gammon mining project.        EPM	10466	in	1995	and	the	       was calculated. These resources   2003.	Tropical	Metals	Pty	Ltd	
                                   tenement was subsequently        were considered uneconomical      was	granted	EPM	14028	over	
The Sailor Tin Prospect is
                                   acquired	by	GTN	Resources	       to mine at the time.              the	area	in	2004.	
20 km south-west of
Herberton. Tin mineralisation      Ltd	in	1997.	In	1998,	Tin	       The Mount Holmes deposit is       Wolfram Camp Mining Pty Ltd,
occurs within the greisenised      Australia NL entered into        being explored by Stonebase       a wholly-owned subsidiary of
upper section of a granitic        a joint venture with GTN         Pty Ltd and Kangaroo Metals Ltd   Queensland Ores Ltd, entered
cusp emanating from the            Resources	Ltd	in	respect	        (EPM	14871)	and	has	potential	    into a farm-in agreement in
granite pluton, where it           of all its north Queensland      inferred resources of 10 Mt       2008	and	is	actively	exploring	
intrudes sedimentary rocks         tenements; that agreement        at	0.07%	Sn	and	0.01%	W	          the permit.


38 Queensland Government Mining Journal Winter 2009
Mount Garnet area                  of	2.3	Mt	at	0.82%	Sn.	The	      NL remapped and re-sampled         mineralisation was intersected




                                                                                                                                          Exploration and Investment
The	Gillian	Prospect,	7	km	        deposit could be open cut but    the skarn exposures in the         in all six holes along a 2500 m
south-west of Mount Garnet, is     the complex mineralisation       mid-1990s and estimated an         strike length. Exploration
a major tin skarn deposit close    makes tin recovery difficult.    inferred	resource	of	666	000	      results suggest a mineralised
to the Palmerville Fault Zone.     However, the low tin             t	at	0.56%	Sn.	Bluestone	          system with a conceptual
It has a large, low-grade tin      price discouraged active         Nominees Pty Ltd applied for       potential	for	80	to	120	Mt	
resource similar to the nearby     development at the time.         MDL	381	over	the	Windermere	       averaging	0.2%	to	0.3%	Sn.
Pinnacles and Ironstone                                             prospect	in	2007.
                                   Strike Exploration Pty Ltd                                          Conclusions
deposits. Mineralisation
                                   farmed into the property in      The Khartoum tin project,
formed through the intrusion                                                                           The use of tin in lead-free
                                   1995. Using past drilling        20 km north-west of Mount
of the late Carboniferous                                                                              solders seems to be assured
                                   data, geological consultants     Garnet, comprises highly
Hammonds Creek Granodiorite                                                                            as the electronic solder sector
                                   Rockcombe	Pty	Ltd	estimated	     fractionated coarse-grained
into reactive calcareous                                                                               is seen as an ‘environmentally
                                   the	resource	to	be	1.8	Mt	       granites, cut by a prominent
sedimentary rocks of the                                                                               friendly’ growth industry in
                                   grading	0.54%	to	0.69%	          east-west fault zone that is
Chillagoe Formation, creating                                                                          the world.
                                   Sn.	In	1998,	Tin	Australia	NL	   infilled by a dolerite dyke that
a complex replacement              confirmed that a significant     extends from the Gurrumba          Even though the world market
deposit rich in fluorine and       cassiterite-rich zone occurs     Ring	Complex.	The	Khartoum	        price for tin has consolidated
iron. Tin mineralisation           at the southern end and          mine was a significant             significantly	in	late	2008,	
is contained in bodies of          reported an indicated            high-grade molybdenum              economic forecasts generally
ironstone forming parts of roof    resource	of	0.5	Mt	at	1%	Sn.	    producer during World War I.       consider that the long-term
pendants in coarse-grained                                          Total production from historic     outlook for tin remains
granites. Tin is present in        Bluestone Nominees Pty Ltd                                          positive. The rally of tin price
                                                                    mines in the western part of
cassiterite and in ‘gillianite’    acquired	MDL	38	in	2004.	                                           recovery in mid 2009 provides
                                                                    the Khartoum area is reported
(tin substituting in the           Metals X Ltd (through its                                           further confidence.
                                                                    as	23	000	t	of	tin-tungsten-
goethite	lattice).                 acquisition of Bluestone
                                                                    copper ore.                        The Collingwood tin mine
                                   Nominees	Pty	Ltd)	acquired	
The deposit was mined up           the deposit in 2005 and          The tin project includes a group   is the only recently-worked
until	the	1960s	for	magnetite	     investigated tin fuming          of hard rock tin occurrences       underground hard rock deposit
for heavy media for tin jigging.   methods for treating the         that BHP Minerals Ltd              in Queensland. Current
                                   complex ore. Consolidated Tin    inspected for Tailmin Pty Ltd      exploration in the Cooktown,
Toledo Minerals Ltd
                                   Mines Ltd currently holds the    in	1980.	Rock	chip	samples	        Herberton, Mount Carbine
commenced exploration
                                   deposit and is re-examining      returned some high tin assay       and Mount Garnet areas is
for base metal and tin
                                   options for development.         results, but no follow-up work     defining significant resources
mineralisation in the early
                                                                    was carried out. Supersorb         that assure the potential for
1970s	and	completed	               The Windermere prospect
                                                                    Environmental NL acquired          the Hodgkinson Province to
percussion and diamond             is	30	km	east-north-east	
                                                                    the project from Friends           continue to be Queensland’s
drilling. Otter Exploration        of Mount Garnet. The old
                                                                    Exploration	Pty	Ltd	in	2006.	      leading tin-producing region in
NL took up the ground in           workings are on top of a small                                      coming years.
1974;	Renison	Goldfields	Ltd	      hill in massive magnetite-       Recent	mapping	by	Auzex	
farmed-in and completed nine       hematite ironstone skarn         Resources	Ltd	under	
trenches	and	16	diamond	           rocks that crop out over a       EPM	14797	has	identified	
drillholes that delineated         length of 250 to 2500 m          a number of greisen zones
three significant ironstone        and width of 50 to 100 m.        and pipes with anomalous
lenses containing the              Six tin-bearing skarn zones,     tin, tungsten, silver and gold.
majority of the cassiterite        termed Zones A to F, have        Rock	chip	samples	assayed	
mineralisation.	In	1976,	          been identified.                 up	to	15.25%	W,	3.78%	Sn,	
Renison	Goldfields	estimated	                                       0.13%	Bi,	438	g/t	Ag	and	3.39	
                                   Renison	Ltd	and	Otter	
that the deposit contained                                          g/t Au. Six drillholes were
                                   Exploration NL mapped,
1	Mt	at	0.7%	to	0.9%	Sn.	                                           completed	in	December	2007	
                                   costeaned and rock chip
                                                                    with funding subsidised by
In	1979,	Otter	Exploration	        sampled these zones in
                                                                    the Queensland Government
upgraded the resource to           1982.	This	work	confirmed	
                                                                    under the Collaborative
2.5	Mt	at	0.70%	to	0.90%	Sn	       the extent of the tin
                                                                    Drilling Initiative scheme. Tin
amenable to open pit mining.       mineralisation and identified
Otter Exploration continued        different tin mineral types,
desk-top pre-feasibility           similar to the Gillian
                                                                    CoNTACT
studies	under	MDL	38,	             mineralisation. The skarns
                                                                    Jimmy Lam I Geoscientist
assessing treatment options        contain	up	to	1.75%	Sn	
                                                                    Geological Survey of Queensland
for low-grade tin, including       and	0.22%	W.	Additional	
                                                                    +61	7	3896	9513		I		jimmy.lam@deedi.qld.gov.au
the gillianite mineralisation.     exploration was carried out
                                                                    www.deedi.qld.gov.au
In	1984,	Otter	Exploration	        under	MDL	40,	which	was	
reported an indicated resource     granted in 1991. Strike Mining


                                                                                  Queensland Government Mining Journal Winter 2009 39

				
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Description: Current company exploration status