Optical Calcite Freeform TC2017

Optical Calcite Freeform Approx. Dimensions: 2.5 x 1.75 x 3 inches Approx. Weight: 420 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 responsible for the incredible displays of rainbows inside many optical calcite pieces. Optical calcite is a very soft material that cleaves rather easily, usually fracturing into rhombohedral shapes. This material has historical significance for its use in sighting equipment for bombardiers and gunners during wartime.