Stelar Metals (ASX: SLB) has reported consistent high-grade assays of up to 28.7% copper from rock chip sampling at its Baratta project in South Australia.
Samples were collected along 3 kilometres of strike between the main historic Baratta mine and east towards North Bore, along a series of multiple strike-extensive parallel gossans.
Baratta is considered highly prospective for sediment-hosted stratabound copper mineralisation and is analogous to the prolific Central African Copper Belt, the world’s second-largest copper-producing province.
Strong sampling
The company confirmed 21 out of 72 samples had returned grades over 10% copper and close to 66% of samples returned grades over 5%.
Rock chip samples were also selected from outcrops of weathered gossan, historic mine spoil and minor excavations.
Stelar had previously collected 1,182 soil samples in June from the central portion of the Baratta copper mine area.
The company used a Niton XL5-plus portable x-ray fluorescence analyser to return highly anomalous copper values along several gossanous horizons.
The values have since been substantiated by rock chip laboratory assays.
Bibliando Thrust focus
The Baratta mine produced copper ore between 1896 and 1904 from a 1.5 km-long zone of stratabound workings in an area splaying off the major Bibliando Thrust structure.
Stelar is planning to conduct an additional round of sampling this month along the 7km strike of the prospective copper zone.
Future work will also focus on the Bibliando Thrust – where several recorded mineral occurrences are located – and the elongated Bibliando Diapir south of the mine.
Mineralised gossans
Stelar’s Baratta tenement is located in the northern part of the Nackara Arc within the Adelaide Rift Complex.
Four distinct, stratigraphically-controlled, continuous mineralised gossans have been mapped to date along the central strike length at Baratta, open to the east and west.
They are believed to comprise quartz, haematite, chalcocite, malachite, azurite, siderite and ankerite, with individual gossans mapped up to 5m in thickness.
Stelar has also identified abundant historical excavations comprising numerous shallow shafts beyond the mined area.
Significant copper mineralisation has also been reported at Wyacca, about 15km west of the tenements.
