Garden Well
Summary
Stage | Production |
Mine Type | Open pit |
Mineralisation | Mixed ultramafic- sediment shear |
Plant type | Crush, grind, CIL |
Throughput | 5mtpa |
Reserve grade | 0.91g/t gold |
Recovery | 88% |
Mine Life | 7 years |
Ore Reserves | 1.01Moz |
Mineral Resources | 2.47Moz |
History
Geology
The Garden Well gold deposit is covered by a Tertiary palaeochannel up to 30m thick and has no surface geochemical response, but does display moderate gold anomalies on the margins of the palaeochannel distal from the deposit. Moderate 8 to 75ppb gold anomalies on the palaeochannel margin were tested with the 2008 Aircore drilling and may represent gold leakage anomalies at the base of the palaeochannel or a truncated surface gold anomaly. Gold mineralisation occurs as oxide ore down to 70m below the base of the palaeochannel and hypogene ore was drilled to a depth of 400m. Gold mineralisation is open at depth. Oxide mineralisation consists of a 70 to 100m wide moderate east dipping gold bearing zone in clay rich residual Archaean saprolite with some sub-horizontal supergene gold developed in the upper part of the saprolite profile. Host rocks are strongly sheared moderately east dipping Archaean ultramafic rocks in contact with overlying moderately east dipping argillaceous sediments. The shear zone continues as primary hypogene mineralisation below the top of fresh rock and is characterised by a 50 to 70m wide strongly altered quartz-dolomite-fuchsite-chlorite-pyrite zone in ultramafic rocks.
Mining is conducted using truck and shovel excavation methods by Mining and Civil Australia Limited who supply the same services at the Moolart Well Gold Mine. The plant design is based on a nominal 4.0mtpa throughput utilising a three stage crushing circuit, a scrubber and a single ball mill followed by gravity and carbon in leach circuits.