MINERALOGY OF GOLD AND SILVER OCCURRENCES IN THE RHYOLITE ORE FROM

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					    MINERALOGY OF GOLD AND SILVER OCCURRENCES IN
       THE RHYOLITE ORE FROM SOLEDAD MOUNTAIN
                                                  for
                                      Golden Queen Mining Co Ltd.
                                           6411 Imperial Ave.
                                 West Vancouver, BC V7W 2J5, CANADA

                                      Attn: Lutz Klingmann, President

                                               SUMMARY
     As integral part of on-going leach testwork evaluating silver/gold recoveries from Ag-Au ores from Soledad
     Mountain (CA, USA), a rhyolite ore sample was submitted for mineralogical study by Golden Queen Co. Ltd.
     The scope of this study was to determine the mineral composition of gold and silver-bearing
     occurrences and to assess its impact on metallurgy.

     The ore composite, grading 0.556 g/t Au and 47 g/t Ag (Table 1) was ground to 70% passing 100 µm and a
     250g-cut was screened into four size fractions (-20 µm, 20-53 µm, 53-100 µm and +100 µm). The –100 µm
     size fractions were subjected to gravity separation and gold and silver mineralogy (Table 2) was established
     based on microscopy and CN leach data (Table 3).

     Results of the current investigation (Table 2) confirmed earlier findings (see Appendix A1) that electrum
     [(Au, Ag)] and native gold (Au) are the principal forms of gold in the rhyolite ore from Soledad Mountain.
     The ratio of electrum/native gold in the ore composite examined is 10:1. A total of 89 grains of
     electrum/native gold were observed and sized. The grain size of electrum varies between 8 and 95 µm,
     whereas that of native gold ranges from 15 to 45 µm. The composition of electrum (SEM-EDX) and
     photomicrographs of both gold carriers are shown in Appendix A3.

     The silver-bearing mineral assemblage (Table 2) consists of acanthite (Ag2S), stephanite ? (Ag5SbS4), native
     silver (Ag), pyrargyrite (Ag3SbS3), and chlorargyrite (AgCl). Acanthite is by far the most abundant silver-
     containing mineral phase, with the other forms of silver only adding a variety to the silver mineralogy of the
     rhyolite ore. A preliminary semi-quantitative SEM-EDX analysis found no mercury (Hg) in the
     acanthite lattice. The grain size of acanthite ranges from 1 to 100 µm (297 acanthite grains sized), with the
     bulk of free grains being in the 20-53 µm interval (Plate 2).

     In conclusion, at the chosen grind fineness of K70=100 µm, 89% of the total gold in the rhyolite ore
     composite occurs as free/exposed electrum and native gold particles (Plate 1) and therefore is
     amenable to direct cyanidation (Table 3). It should be noted however, that the high silver content of
     electrum can adversely affect the leach kinetics at low free cyanide levels. The balance of gold (11%)
     is present as either enclosed leachable or refractory gold (in pyrite) and determination of its real nature was
     beyond the scope of this study.

     Cyanidable silver (78%, Table 3) in the rhyolite ore at the current grind fineness is accounted for by
     free/exposed acanthite (Plate 2), with the other silver minerals occurring in trace amounts. As the mercury
     content of acanthite was routinely below the detection level of SEM-EDX analysis, no interference during
     leaching is expected as a result of coatings on acanthite particles. The exact form of unleached silver
     (22%) is unknown at present; it may occur as either enclosed (but leachable) acanthite (see Appendix A3)
     or refractory silver (possibly as Ag-bearing pyrite and/or argentojarosite, [AgFe3(SO)4(OH)6]). A limited
     number of SEM-EDX analyses carried out on pyrite and jarosite grains found no silver at a limit of
     detection of 1 wt.%, which would favor the former mode of occurrence of unleached silver, however more
     work is needed to unequivocally resolve this issue.




AMTEL report 03/39                                                      Prepared by: AMTEL Ltd.
Oct. 31, 2003                                                                                 AMTEL
                                             LIST OF CONTENTS
                                                                               Page


LIST OF TABLES

Table 1: Au and Ag Assays of Rhyolite Ore                                       3
Table 2: Gold and Silver-bearing Mineral Assemblages in Rhyolite Ore            3
Table 3: Gold and Silver Extraction from Rhyolite Ore                           3


LIST OF PLATES

Plate 1: Gold Deportment in Rhyolite Ore                                        4
Plate 2: Silver Deportment in Rhyolite Ore                                      5


APPENDICES

A1 Correspondence
A2 Reported Assays by ALS Chemex
A3 Composition and Photomicrographs of Gold and Silver Minerals




  AMTEL report 03/39                         Page 2 of 5
                                                                       AMTEL
                  Table 1: Au and Ag Assays of Rhyolite Ore (Solidad Mountain)


                                                  Au (g/t)          Ag (g/t)

                                                   0.531                  46
                                                   0.511                  41
                                                   0.625                  54

                                                 Avg. 0.556               47




         Table 2: Gold and Silver-bearing Mineral Assemblages in Rhyolite Ore

                                                                           Ag Content        No of grains
              Mineral(1)                         Mineral Formula
                                                                             (wt.%)         characterized

              Au assemblage

              •   Electrum                             (Au,Ag)                  41                 79
              •   Native Gold                            Au                      2                 10


              Ag assemblage

              •   Acanthite(2)                         Ag2S                     87                 297
              •   Stephanite ?                        Ag5SbS4                   74                 12
              •   Native Silver                         Ag                      100                 5
              •   Pyrargyrite                         Ag3SbS3                   60                  2
              •   Chlorargyrite                        AgCl                     75                  1
       (1)
             Minerals printed in green are readily cyanidable, while these in orange are sparingly cyanidable.
       (2)
             The presence of Hg in acanthite lattice can create interfering coatings.




             Table 3: Gold and Silver Extraction(1) from Rhyolite Ore (K70~100 µm)

                               Head (g/t)             CN Leach Res. (g/t)             Recovery (%)
                          Au                Ag          Au               Ag           Au          Ag

                         0.556              47         0.061             10.3         89          78

                   (1)
                         24-hour intensive cyanidation with 5g/t NaCN.




AMTEL report 03/39                                 Page 3 of 5
                                                                                                          AMTEL
 Plate 1: Gold Deportment in Rhyolite Ore (Soledad Mountain)




                                                       0.556 g/t Au
                                                   Enclosed/refractory Au

                                                            10.8%


                                   Free Au     32.0%
                     80                                             57.2%
                                                             Exposed Au
     Abundance (%)




                     60


                     40


                     20


                      0
                          -20   20-53   +53
                          Grain Size (µm)




AMTEL report 03/39                            Page 4 of 5
                                                                            AMTEL
 Plate 2: Silver Deportment in Rhyolite Ore (Soledad Mountain)




                                                                      47.0 g/t Ag
                                                     Enclosed/
                                                     refractory Ag

                                                                      21.9%


                                                         Free Ag   9.4%

                                     100
                                                                               68.7%
                                     80
                                                                              Exposed Ag
                     Abundance (%)




                                     60


                                     40


                                     20


                                      0
                                           -20   20-53   +53
                                           Grain Size (µm)




AMTEL report 03/39                                   Page 5 of 5
                                                                                 AMTEL

				
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