Archer has several copper prospects at various stages of exploration.
The Company's copper projects are all located in South Australia and include, Spring Creek (EL 5440); Worlds End (EL 4230); North Cowell (EL 4277); Emu Plain (EL 4693) and Blue Hills (ELA 2015/00233).
The historic Spring Creek copper mine is located 30km south of the township of Wilmington, South Australia. Copper mining ceased in 1918 when the mine de-watering pump failed and the mine flooded. Copper carbonates exist on the surface above the mine and within the backs and walls of the un-worked sections of the drives. Underground face sampling on the uppermost level of the historic Spring Creek Copper Mine confirmed the presence of significant copper mineralisation peripheral to the former production stopes.· Sampling by Archer identified a ≈2% Cu halo consisting of copper carbonate (malachite and azurite) outside of the main stopes including: 2m @ 1.8% Cu across drive 1; 4m @ 3.0% Cu across drive 1a; 10m @ 1.3% Cu along drive 2 and 12m @ 1.9% Cu along drive 3a.
Worlds End has two potentially significant copper targets; Robertstown and Mimic. At Robertstown cuprite (Cu2O) was identified in highly ferruginous gossan.Also of importance was the identification of marker unit NMS 9, which has been identified as a critical marker unit for copper mineralisation. Mineralisation being modeled is that of a deposit similar to that of the Burra, Monster Mine (MM) that had recorded production of 86,000 tonnes of copper taken from largely copper carbonate-rich ores.
At North Cowell potential exists for an IOCGU deposit, as the Hiltaba granite has been mapped 20km to the east of the tenement. Work to date has been limited to reconnaissance rock chip sampling around areas of known mineralisation, with peak values of 151,000ppm (15.1% Cu) from a prominent ridge.
Emu Plain hosts the historic Emu Plain copper mine that was last worked in the 1950s. In 2011 Archer conducted a three hole RC drill program with results of: 37m @ 0.13% Cu and 4.2g/t Ag from 0 to 37m in EPRC11_001 (EOH), 60m @ 0.11% Cu and 1.0g/t Ag from 0 to 60m in EPRC11_002 and 10m @ 0.50% Cu, 6.9g/t Ag and 600ppm Mo from 27 to 38m in EPRC11_003. Whilst all three drill holes each intersected broad zones of highly anomalous copper mineralisation it is believed that the holes were drilled in the footwall of the main copper lode which is believed to have been at least 7m in width and grading several percent copper.The scale and intensity of alteration suggests that the drilling intersected part of a much larger alteration and mineralisation system.
At Blue Hills initial field reconnaissance by Archer sampled spoil piles surrounding the historical workings. The copper appears in workings that follow the basal contact of the Tapley Hill Formation. The copper occurs with quartz and wall rock alteration suggesting an igneous source, this is supported with elevated Be and REE’s. Archer believes that potential does exist down dip or along strike (under cover) for discoverable economic copper.