SOAPSTONE IN RAJASTHAN by F77WqH0

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									                       SOAPSTONE IN RAJASTHAN
INTRODUCTION
Soap stone, Talc and Steatite are the ,three different terms used for one and the same
mineral. The term talc refers ideally to a very pure hydrous magnesium silicate (3 MgO
Si02H2O) which has a theoretical chemical composition of 63.5% Si02, 31.7% MgO and
4.8% H2O. Soapstone is a massive, soft, greenish talcose rock which is a mixture of talc
and various other magnesium silicates. Steatite (some times termed lava talc) is a compact,
massive talcose rock with no visible grains. The inferior and hard variety of soapstone is
called Potstone.

Talc is an alteration product of original or secondary magnesium minerals or rocks
resulting from mild hydrothermal metamorphism, perhaps aided by mild dynamic
metamorphism. Talc deposits are generally associated with carbonate rocks having higher
magnesia content like dolomite and magnesite, and rarely with marble & limestone.
Contact zones of basic and ultrabasic intrusives also serve as good locales for talc deposits.
The occurrences of talc are widely distributed in the country in Andhra Pradesh, Bihar,
Gujrat, Karnataka, Madhya Pradesh, Maharashtra, Orissa, Tamil Nadu, Rajasthan &
Uttarpradesh. However at present the exploitation of the mineral is confined to Anantapur,
Chittor & Cuddapah districts of Andhra Pradesh; Hazaribagh and Singhbhum districts of
Bihar, Sabarkantha district of Gujarat, Jabalpur and Narasingpur districts of Madhya
Pradesh, Bhandara district of Maharashtra ; Ajmer , Alwar, Karauli, Sirohi, Sikar,
Rajsamand, Udaipur, Dausa, Banswara, Dungarpur, Jaipur and Bhilwara, districts of
Rajasthan; and Almora & Pithoragarh districts of Uttar Pradesh.

OCCURRENCE IN RAJASTHAN

Rajasthan is the leading producer of Soapstone in the country. There are 335 mining leases
for soapstone in the state and about 525160 tonnes was produced during the year 1997. The
description of the deposits in Rajasthan is given below.
RAJSAMAND DISTRICT
Usan-Kagmadar-Sangat-Kalora- Rabcha-Oden belt This belt runs from Usan in SW to
Oden in NE over a strike length of 29 kms. The soapstone mineralization is distributed in
two distinct zones and is associated with dolomitic limestone of Aravalli age and quartzites
of Pre-Aravalli age. Soapstone occurs as lenses and lenticular pockets of varying thickness
and sizes, usually ranging between 1 to 5 mts. in width and 10-15 mts in length. Generally
it is reddish white to white in colour. The inferred reserves are 0.890 million tonnes. The
important working deposits in this belt are Usan, Gorach, Kalora, Rabcha and Unwas.
UDAIPUR DISTRICT
(i) Orda- Deopura-Dingri-Nathara-ki-Pal belt
This belt is about 40 km. SE of Udaipur and runs from Orda-Deopura to Nathara-ki-Pal
over a distance of 12 kms. Here soapstone is associated with talcose schist and dolomitic
limestone of Aravalli age. The soapstone is found to occur as lenses and veins varying in
length from 18 to 90 metres and in thickness from 2 to 15m. The soapstone is massive as
well as foliated in nature and having white to pale green colour. Inferred reserves are 0.5
million tonnes.

(ii) Salumber- Bend-Sajela- Lohangi-Pandla- Deola belt
This is the most important belt which runs from Salumber in NW to Deola in SE over a
strike lengh of 40 km. The soapstone mineralisation is confined to dolomitic lime stone
belonging to Aravalli age. Soapstone mineralisation is in the form of lenses and lenticular
veinsextending in length from 100 to 400 m. and in width from 0.2 to 25 m. The soapstone
is generally of very good quality having pure white to light green colour. Inferred reserves
are 0.99 million tonnes.
(iii) Undithal-Rathora-ka-Gurha-Bansra-Jharol belt This belt extends from Undithal in
SE to Jharol in SW over a distance of 34 km. The soapstone is associated with Post
Aravalli ultrabasic intrusives. Soapstone occurs as swelling & pinching irreqular veins &
lenses. varying in length from 7 to 48 m. and in thickness from 0.5 to 8 m. The inferred
reserves are 0.536 million tonnes.

(iv) Rikhabdeo - Chiklan- Khojawara Mundwara - Chhani belt
This belt runs from Rikhabdeo in NW to Channi in SE over a length of 25 km. The
soapstone is associated with Post-Aravalli ultrabasic intrusives and occurs as irregular
leases and veins varying in length from 30 to 100 mts and width from 1 to 3 m . It is of Pale
green to greenish-white colour and is normally massive. The inferred reserves are 0.570
million tonnes.
(v) Rikhabdeo-Kagdar- Kalyanpur belt
This belt runs from Rikhabdeo in SE to Kalyanpur in SW over a 20 km. length. The
soapstone is associated with Post Aravalli ultrabasic intrusives. The mineralisation exhibits
pinching and swelling tendency. The soapstone is of flaky type varying in colour from pale
green to greenish white. The inferred reserves are 0.654 million tonnes.




DAUSA DISTRICT
In Dausa district the soapstone deposits are located. at Degota, Jharna, Kalajpuri Raylala,
Dhaniawara and Geejgarh-Ranoli Achalpur areas.
The soapstone deposits at Degota- Jharna, Kalajpuri, Dhaniawara and Rayala are associated
with dolomitic limestone belonging to Railo Group of Delhi Supergroup. The soapstone
occurs in the form of lenses and veins. The talc bodies in many cases are thin near the
surface and widen at depth. The thickness varies from 1 mt to 6,mt. and persists beyond the
excavated depth of 25 mts. The Jharna mines are open cast where as Degota mine is a
underground mine in which working ,has reached to 140 metres depth.
Talc is pale greenish to light green and white in colour and foliated. The inferred reserves
of 9.2 million tonnes of soapstone have been reported from DegotaJharna belt.
AJMER DISTRICT
The soapstone occurrences are found near villages Hahmdi, Gegal Akhari, Lachipura
Sendra, Chitar and Chapaid.
The soapstone in the area is associated with talcchlorite schist, an altered product of basic
intrusives within the quartzite, phyllite and garnetiferous mica schist belonging to Ajabgarh
group of Delhi Supergroup.
Soapstone occurs as thin veins/lenses in an en-echelon pattern with in the talc-chlorite
schist. The thickness of individual veins vary from a few centimetres to about a metre. The
soapstone mined from the area is mostly of DDT grade.
ALWAR DISTRICT
The soapstone deposits in Alwar district are located at Ratangarh, Nagalheri, Baisawas and
at Bhugarbha. The soapstone occurrences are confind to limestone or dolomitic limestone
belonging to Railo Group. The soapstone occurs mainly as veins, lenses or lenticular
pockets of varying dimensions. The veins vary in thickness from few centimetres to one
mt. The soapstone is mostly of paper grade.
BANSWARA DISTRICT
The Soapstone mineralization is spread around Jagpura, Tartai, Bhukia, Mewal, Kundali,
Kondri, Duduka, Mandela jamboi, Himmat Singh ka-Gurha and Rhaniya area. It is
associated with the rocks of Aravalli and Delhi Supergroup represented by dolomitic
limestone, ultrabasic and talc-chlorite schist. It occurs as narrow veins ranging in thickness
from few centimetres to 2 metres. Soapstone is foliated to massive and is generally white,
Pale green, greenish white and dull grey in colour. The talc produced from the area is
reported to be of cosmetic grade. About 0.27 million tonnes of reserves have ben estimated
from these areas.
BHARATPUR DISTRICT
Soapstone mineralization is located near village Nidar ( teh. Bayana), Mangren (feh. Ber),
Bilung (teh. Kama ). The soapstone is of low grade.
CHITTORGARH DISTRICT
In Chittorgarh district soapstone occurrences are reported near village Chiklar (Teh.
Pratapgarh) and Sukhadia (Teh. Dungla).
DUNGARPUR DISTRICT
The important deposits of soapstone are located in a 35 kIn. long belt from NNW of
Rikhabdeo to SSE of Dungarpur near village Deval, Balwara, Thana, Piploda, Deopur,
Panchpura & Bodawali etc.
The soapstone deposit$ are mainly associated with serpentinites and dolomites along
fractures and shearzones as small and large lenticular patches, elongated bodies and thin
narrow impersistant bands. The individual veins have been found to continue over a strike
length of nearly 50 mts. down to a maximum depth of 20 mts.
In the area 60% of the material is talc grade. 30% paper grade and only 10% is D.D.T.
grade.
JHUNJHUNU DISTRICT
In the district occurrences of soapstone are reported from Dhani (teh. Khetri) Gudha and
Kho area (Teh. Udaipur wati)
KARAULI DISTRICT
The soapstone in the district occurs in Morra-ka-Dungar ridge of Toda Bhim tehsil. It is
located 27 km. North-West of Hindaun, situated on the NagdaMathura broad gauge section
of the W.R. Talc deposits in the Morra-ka-Dungar ridge are known for the last 125 years
and these have been worked on a small scale ever since. Between the village of Dhaota and
Morra which are about 8 kIn. apart the talc deposits have been exposed at as many as seven
localities near Dhaola, Dwain, Kamalpura, Rajuli, Giarhi, Pura & Mora. Of there the
deposits of Dwain, Rajauliand Gorhiare fairly large. Most of the depo$its in this area occur
in the basal part of the massive quartzite (Alwar group)
The talc occurs in lenses which vary in width from less than a metre to 20 metres and are
exposed over lengths varying from a few metres to 40 metres. The talc is generally pale to
light green and pale greenish white in colour, cleaved to locally compact & massive. The
'indicated' reserves of talc from Dwain Rajauli & Garhi areas have been estimated at about
0.107 million tonnes for depth varying from 8m to 30m. along dip.

BHILWARA DISTRICT
The soapstone deposits in Bhilwara district are one of the bestgrade and are located at
Ghevaria, Chainpura, Kishangarh Bagwara, Asanmata, Bhilaikheda, Kacholia, Amargarh,
Chhabria, Abhaipur, Bhunagar and near Jahajpur.
The Ghevaria soapstone deposit in the single largest deposit in the country which is
estimated to contain 20 million tonnes of reserves.
The soapstone occurrences in this district are confined to dolomitic limestone/quartzite
belonging to PreAravali Group. Two parallel ridges of dolomitic limestone extend from
Ghevaria in the south west up to Jahazpur in the north east for a distance of more than 32
kIn. All the important deposits of soapstone in this area are located on these ridges. The
soapstone occurs mainly as veins, lenses and lenticular pockets of varying dimensions. The
soapstone is generally of pale greenish to light green in colour. Near surface it is off-colour
and stained yellow and red but at depth quality improves and it is free from ferruginous
materials.
TONK DISTRICT
In Tonk district soapstone has been reported from Chandsen and Ghati (feh. Malpura) and
Niwai village.
PALl DISTRICT
In this district soapstone is associated with asbestos in ultrabasic rocks near village manpur
and Kanotia in Tehsil Raipur.
USES
Talc is used mostly in a fine-ground state although soapstone is used in massive or block
form. There are many industrial applications for ground talc but major consumption is
limited to less than a dozen industries. Talc is used as a filler material in the manufacture of
high quality paper where it aids in dehydration of the pulp, improves characteristics,
reduces the tendency of papers to yellow and assures a well bonded surface to promote ease
of printing. For use in the paper industry talc must be free of chemically active compounds,
have a high reflectance, possess high retention characteristics in the pulp and be free of
abrasive impurities. Micronized materialprovides a high-gloss finish on coated papers.
The ceramic industry utilizes very finely ground talc which increases the translucence and
toughness of the finished product and aids in promoting crack-free glazing . For use in
ceramics, talc must be free of impurities which would discolour the fired product. High-
quality talc is used as an extender pigment in paints. Specifications for a talc pigment,
relate in the chemical composition colour, particle size oil absorption and consistency of
and dispersion. A low content of carbonates , a nearly white colour, a fine particle size with
controlled particle size distribution and a specific oil absorption are important, however,
because of the variety of paints precise specifications for talc pigments are generally based
on agreement between consumer and supplier, paint characteristics influenced by the use of
talc as an extender are gloss, adhesion, flow, hardness and hiding power.
Talc is well known for its use in pharmaceutical preparations and cosmetics. It is the major
ingredient in face, baby and body powders. Finely ground, high-purity material is used as a
filler in tablets and as an additive in medical paste, creams and soaps. Material used for
these purpose should be free of deleterious chemical compounds and abrasive impurities.
Lower grade talc is used as a dusting agent for asphalt roofing and gypsum board, as a
filler in dry wall sealing compounds, as a filler material in floor tiles, in asphalt pipeline
enamels, in auto body patching compounds, as a carrier for insecticides and as a filler or
dusting compound in the manufacture of rubber products.
Other application for talc include use in cleaning compounds, polishes, electrical cable
coating, plastic products, foundry facings, adhesives, linoleum textile, and in the food
industry.
Particle size specifications for most uses require the talc to be (-)325 mesh. The paint
industry demand from 99.8 to 100 %, (-)325 mesh. For rubber, ceramics, insecticides and
pipeline enamels, 95 percent, (-) 325 mesh is usual. In the wall tile industry 91 per cent
,(-)325 mesh is generally required. For roofing grades the specification is about (-)80 mesh
with a maximum of 30 to 40 percent, minus 200.
Soapstone has now only very limited use as a refractory brick or block, but because of its
softness and resistance to heat it is still used by metalworkers as marking crayons. The case
with which it can be carved makes it an excellent artistic medium..

								
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