Augite

$110.00

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Black crystals of augite, this the variety often called jeffersonite, measuring to 1.0 cm in size embedded throughout a massive calcite matrix. The specimen comes with a previous label from the collection of Ray DeMark. Located in Franklin, Sussex County, New Jersey, Trotter's Dump is a famous historic mining area situated within the prolific Franklin Furnace ore body. The region's unique geology features highly metamorphosed Precambrian limestone and skarn deposits that underwent complex hydrothermal recrystallization, creating one of the most mineralogically diverse sites on Earth. First worked during 19th-century commercial zinc mining at the Trotter Shaft, the surrounding dump piles quickly became a renowned destination for specimen collectors. Among its notable mineral occurrences is jeffersonite, a rare dark green to dark brown manganese- and zinc-rich variety of augite. Discovered in abundance at this location, jeffersonite formed large prismatic crystals in marble and calc-silicate host rocks, making Trotter's Dump a classic type locality for specimen collection.