Cassiterite (rare prismatic crystal)

Item Description

Cassiterite is a well-known tin oxide mineral, found in many localities around the world. The majority of the Cassiterite crystals you'll see will feature cyclic twins, but occasionally a piece like this will surface, showing an uncommon elongated prismatic habit (with no twinning). This piece is a sharp, highly lustrous, jet-black, tetragonal prism with two pyramidal terminations, and no matrix. The piece is unfortunately contacted on both ends, and it's not complete on the back, so it's not damage-free, but it's still an attractive example of a lesser-seen habit from this fairly well-known tin deposit in China. Ex Dr. Stephen Smale Collection. Along with amassing one of the finest private mineral collections in the world, Steve is a renowned mathematician. His accomplishments include being awarded the Fields Medal in 1966 along with being the awarded the Wolf Prize in mathematics in 2007. You can read Steve's bio on the Mineralogical Record website ( https://mineralogicalrecord.com/biographies_labels/smalestephen/ ) or on Wikipedia.