Cassiterite ("drillbit" twins) with Quartz

Item Description

Cassiterites from Huanuni are not easy to obtain. The mine at Huanuni is one of the largest tin mines in Bolivia and is a real sight to see. This mine is better known for its phosphate species, but some of the more unique and attractive Cassiterite specimens are found there. This specimen comprises several fine quality, sharp, lustrous, black prismatic tetragonal crystals (some of which show "drillbit" twinning) measuring up to 1.1 cm with a small amount of white Quartz. The habit of the crystals is a dead giveaway that it's from Huanuni, and nearly every other notable mine in Bolivia produces Cassiterites with cyclic twins and not prismatic crystals like this.