Golden Grove July 2015 History of Golden Grove
1971 -1979 • Gossan Hill underground, Gossin Hill Open Pit and Scuddles Underground discovered.
1990 • First production from Scuddles underground mine (capacity 800kt/a).
1991 • Normandy Poseidon completes acquisition of Golden Grove from Australian Consolidated Minerals.
1997 • First production from Gossan Hill underground mine.
2002 • Acquired by Newmont Australia Ltd.
2005 • Sold to Oxiana Limited for A$265 million.
2008 • Transferred to OZ Minerals with the merger of Oxiana and Zinifex.
2009 • Minmetals acquires OZ Minerals assets with the exception of Prominent Hill.
2 2012 • First production from Gossan Hill copper oxide open pit. Overview
Location: Western Australia, Australia Ownership: 100% MMG
Mine: Underground (sublevel open stope) & Open Cut.
Throughput: 1.7 Mtpa, mine, crush, grind, float.
Product: Zinc concentrate, Copper concentrate, 2014 Revenue by commodity Lead precious metals concentrate. 6% Mine Life 2021 1% 9%
20%
64%
Copper Zinc Gold Silver Lead 3 Golden Grove – Site layout
4 Geology – Volcanogenic Massive Sulfide (VMS) deposit
Characteristics of VMS Deposits
Size <1Mt to 50Mt to giant deposits (500Mt) e.g. Kidd Creek, Brunswick 12, Neves Corvo.
Polymetallic, Golden Grove Zn, Pb, Cu, Ag, Au & Magnetite.
Stacked Deposits, Repetition through rock sequence.
Occur as clusters within belts (3 to 6 kms separation) Mt Read Volcanics of Tasmania, Iberian Pyrite Belt, Green Tuff Belt of Japan.
Present day analogue of VMS deposits are Black Smokers.
5 Mine overview
Gossan Hill Underground Mine
AB Zinc Open Pit Tryall > Lead/Zinc (Pb/Zn) ore contains: A Copper
- Sphalerite (ZnS), Galena (PbS), Ag, Au. C Copper Camberwarra > Copper (Cu) Ore. Upper Q Copper 500m DEEP Catalpa - Chalcopyrite (CuFeS2). Amity
Q Copper Ethel (Lower)
Hougoumont 1000m DEEP Hougoumont Hangingwall Xantho Lower Amity
Oizon
Hougoumont Extended
1500m DEEP Gossan Hill 2015
6 Mine overview
Mine Southern Portal Central Northern Shaft Scuddles Underground Mine Downcast Downcast Upcast
> Lead/Zinc (Pb/Zn) ore contains:
- Sphalerite (ZnS), Galena (PbS), Ag, Au.
> Copper (Cu) Ore.
- Chalcopyrite (CuFeS2). 500m DEEP
Batavia
1000m DEEP
SCUDDLES 2015
7 Mine overview
Gossan Hill Open Pit
> Copper ore contains:
- Variety of Cu sulphide and Cu oxide minerals.
- Native Cu. - Au.
8 Resource Expansion
> Seven underground rigs. > One surface multi-purpose rig.
2015 Drilling by type
Grade Control
Delineation
Resource Definition
Near Mine Exploration
9 Metallurgy flow sheet
Pebble Crusher
Ball Mills x 2 Gossan Hill Stockpile
Scuddles Stockpile Copper/Zinc Flotation Lead Flotation
Zinc/Copper Thickener HPM Thickeners Zinc/Copper Clarifier Tailings Minefill
Thickening and Filtration Thickening and Filtration
10 Gossan Hill – ROM, Crusher & Stockpile
1. Raw underground ore on the Run-Of- Mine (ROM) gets pre-crushed by mobile equipment.
2. Ore is fed through a Jaw Crusher.
3. Ore is stockpiled and fed to grinding Run-Of-Mine Pad circuit.
11 Primary Crusher Gossan Hill Stockpile Scuddles – Hoist, Crusher & Stockpile
Secondary Crusher Scuddles Hoist
1. Scuddles Hoist – hoists crushed ore from underground.
2. Ore is crushed by a cone crusher.
3. Ore is stockpiled and conveyed to the main plant feed conveyor.
12 Scuddles stockpile
Grinding
Semi-Autogenous Grinder (SAG) > SAG mill (1.5MW).
> Pebble crusher.
Ball Milling Circuit > Ball Mill 1 (1.5MW).
> Ball Mill 2 (400kW).
Ball Mill 1
13 Semi-Autogenous Grinder Dewatering
4x Thickeners
14 2x Disc filters 1x VPA pressure filter Tailings – Dams, CHF Mine Backfill
Mill tailings are directed to two locations:
> Cement Hydraulic Fill (CHF) Plant supplies backfill to Gossan Hill underground mine.
> Tailings Storage Facilities.
Tailings Storage Facility 3 Cement Hydraulic Fill Plant Marketing
Products: Zinc concentrate Copper concentrate Lead high precious metals concentrate
Production: 2015 guidance (metal in concentrate) Zinc: 40 -55 kt contained zinc Copper: 21 -24 kt contained copper
Product sales: Smelters in Asia and Europe • Concentrates are trucked 280kms by road from Golden Grove mine site to the Port of Geraldton. • Road transport is through Giacci Transport who operate 7 dedicated road trains. (14 movements a day =1,400wmt) • The storage shed at Geraldton is owned by MMG on land leased from the Geraldton Port Authority. • Ships chartered in-house by MMG via COA with Ausbulk. 16 Marketing
Zinc Concentrate > Zinc grade approximately 50% and ‘clean’ of impurities.
> Silver content just above payability thresholds.
> Primarily concentrate sold to smelters in Japan, Korea and Thailand.
Copper Concentrate
> Copper grade approximately 20%. > Contains Silver along with payable Gold.
> Primarily concentrate sold to smelters in China, Korea and Japan.
Lead Concentrate containing Copper and high precious metals
> Lead grade approximately 30-35%, Copper 5-10% and payable Silver and Gold.
17 > Primarily concentrate sold to refineries in Europe.
18