PYRRHOTITE on DOLOMITE, ISSOM RL Renison Bell Tin Mine TASMANIA (small cabinet)

From the ren deep section of the mine and discovered in 1989. It was a big discovery. This is maybe the only specimen left on the market; at least it is one of the better specimens. Classic hexagonal crystals up to 10 mm.

Pyrrhotite is a prevalent magnetic iron sulfide mineral (Fe₁₋ₓS) characterized by its bronze-brown hue, which often shows signs of tarnishing. This mineral serves as a significant source of nickel and has historical importance in iron production. However, it is infamous for its role in the deterioration of concrete and the cracking of foundations, particularly in regions like New England, where its oxidation leads to expansion. Commonly referred to as "magnetic pyrite," pyrrhotite exhibits a metallic luster, a grayish-black streak, and a hardness rating of 3.5 to 4. It can be found in igneous and metamorphic rocks, as well as in hydrothermal veins, frequently occurring alongside minerals such as pentlandite, pyrite, and chalcopyrite.