Mine Technical Services

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Mine Technical Services
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Departmental Responsibilities

• GRADE CONTROL SAMPLING
• EXPLORATION
• ORE RESERVE MODELLING

• GRADE CONTROL SAMPLING
• EXPLORATION
• ORE RESERVE MODELLING

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History
1924- Platreef Discovered Dr Hans
Merensky 1930s- Small mining operations ceased
due to economic depression 1966- JCI Focuses
exploration operations on Sandsloot, Vaalkop and
Zwartfontein 1992-Waste stripping on Sandsloot 12
February 1992- First Blast Sandsloot 22 August
2002- First Blast Zwartfontein
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PLATREEF Outcrop and Target Areas
Tweefontein North
Tweefontein Hill
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Emplacement of the Platreef
Magma Cu, Ni, S, PGM
Transvaal Sequence (Ca,Mg)CO3
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Distribution of rock types and ore zone
Norite
Pyroxenite
Calc-silicate
Parapyroxenite
Dolomite
RS/PPLJan2000/06
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Geological Cross-Section
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Generalised section from Macalacaskop in South to
Nonneworth in the North showing the footwall
lithology changes.(Kinnaird et al.,2005
Mineraluim Deposita in press)
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Airborne magnetic survey
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Stratigraphic Comparison
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Regional Stratigraphy of Platreef
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Base Metal Sulphides

• Pyrrhotite, FeS
• Pentlandite, (Fe,Ni)9S8
• Chalcopyrite, CuFeS2
• Coarse grained, mm in size
• Godlevskite (Ni7S6)/Millerite (NiS)
• Valleriite CuFeS21.5(Mg,Al)(OH)2
• Fine grained, generally lt100µm

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PGM Types - Platreef vs Merensky
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Base Metal Sulphides
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PGM Au Recoveries on the Platreef
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GRADE CONTROL
Ensure optimal extraction of the orebody by
rendering the following service 1.SAMPLING 2.COMP
OSITING 3.STAKING 4.LOADING 5.STOCKPILING 6.CRUSHE
R FEED BLENDING 7.ORE CHARACTERISATION
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Composite Staking
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Staking after a blast
W
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Composite Loading
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Conclusions

• Footwall geology has had a major effect on the
  mineralogy (silicate, base metal and PGE) of the
  Platreef
• The different rock types have major mineralogical
  differences which has affected the hardness and
  metallurgical performance of the ores.
• Base Metal Sulphide and PGM type and grain sizes
  are affected by the rock type.

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THE END Thank you