Fluorite With Quartz and Hydrocarbons
Shipp & Covert Mine, Rosiclare Level, Cave-in-Rock, Hardin Co., Illinois, USA
Cabinet, 14.5 x 8.1 x 7.6 cm
Ex. Ross Lillie

From a rare location where the drusy smoky quartz is typical of the deposit mined out in the 1930s (and is caused by hydrocarbons within), this specimen features large cubes of lustrous and translucent, purple fluorite, to 4.8 cm across. The fluorite crystals clearly exhibit stepped growth and are emplaced on drusy smoky quartz which grew on a limestone matrix. Discovered in the summer of 2003 in a lucky find at the old mine, this is a highly unusual specimen for the district, and a pretty piece on its own merits. RCL 1364.