Copper was discovered at Blinman by a shepherd, Robert Blinman in 1859. Copper mining occurred in the area from around 1862 through to 1918 when the ore ran out. In total around 10,000 tonnes of copper were removed from 200,000 tons of ore from the mine.
A diapir is a type of geologic intrusion in which a more mobile and ductily deformable material is forced into brittle overlying rocks. Depending on the tectonic environment, diapirs can range from idealized mushroom-shapes in regions with low tectonic stress to narrow dikes of material that move along tectonically induced fractures in surrounding rock.
The copper deposit at Blinman occurs within the Blinman Diapir. The Blinman Diapir occupies approximately 44 square km in the central part of the Flinders Ranges. The diapir consists of a mass of brecciated and crumpled sedimentary rock, believed to be of Proterozoic Willouran age, intruded into younger Sturtian rocks. Within the breccia, blocks of varying rock type range in size between 1.5 km and one metre. They include siltstone, sandstone, shale and dolomite, with volcanics and associated tuffs common. Mineralisation is associated with melaphyre, dolerite and dolomite rock types. At the Blinman Mine, stratiform chalcopyrite, bornite and pyrite, together with cross-cutting veins of primary sulphides, occur within 'mine-type' dolomite. Bright green and blue copper carbonate minerals, Malachite and Azurite are also found in the mine.
To complete this earthcache you will need to take a Heritage Blinman mine tour. Please provide answers to the following questions.
-What colour is the most common copper mineral in the mine?
-How was the copper ore mined?
-In "The Chapel" what feature can be seen on the right side of the chamber?
There is a fee to take Heritage Blinman mine. For current fees and booking details check the following URL, http://www.heritageblinmanmine.com.au/tour-guidelines