I collect this in 1968 while mapping underground at the Caribou mine. In specific, there was a location in the mine where the massive sulfide layers were cut and displaced by a fault zone, creating an offset of more than 30 m. The stiff sulfide layers were fractured and broken, and locally polished and slickenlined. I like the fact that this is naturally polished metal.
The focus of my dissertation research in the Bathurst district of New Brunswick was a massive sulfide deposit. At issue was whether the massive sulfide deposit (mainly pyrite but with sphalerite, chalcopyrite, and galena) was a hydrothermal ore deposit created by fluids from depth that migrated up along a fold hinge and selective replaced country rock; or was a stratabound volcanic exhalative deposit formed originally on the seafloor bottom in a volcanic arc setting. At the time (late 1960s), the battle between ‘epigenetic’ vs ‘syngenetic’ origin of stratabound sulfide deposits was raging. My approach was compare and contrast the structural histories of the massive sulfide deposit versus the country rock, to determine whether they had experience the exact same tectonic history or not. My approach was mapping and detailed structural analysis. This particular specimen reveals a late stage brittle faulting of massive sulfide ore. It attracted my attention because of the beautiful frictional (fault) polish and presence of slickenlines.
Age & Formation
Tetagouche Group of Ordovician age, ~420 Ma.