86g Optical Calcite Freeform TC2101 carving Thulite butterfly cabochon set in

Thulite butterfly cabochon set in sterling silver

Weight: 55 grams

It may contain crystals called phenocrysts

is composed of Iron Sulfide

with small pyrite crystals scattered throughout

86g Optical Calcite Freeform TC2101 carving Thulite butterfly cabochon set in86g Optical Calcite Freeform Approx. Dimensions: 1. 25x1x2 inches Approx. Weight: 86 grams Locality: Maharashtra, India Optical calcite is also referred to as Iceland Spar because of its first discovery in Eskifjord, Iceland. It is typically colorless, and exhibits the optical phenomenon of double refraction where an object viewed through the calcite will appear doubled. Double refraction, or birefraction, is also called birefringence and is also