Calcite (var: Iceland Spar) (ex Kay Robertson Collection)

Item Description

A classic specimen of what was named "Iceland Spar" after the first reported locality in Helgustadir Mine, Iceland which dates back to 1669! Iceland Spar is defined as an optic grade Calcite, but is usually found in rhombic cleavages. THIS specimen is actually a beautifully well-crystallized scalenohedron, with wonderful internal gemminess and an almost silky colorless interior. The crystal is nearly complete (cleaved on the bottom), and the spot on the lower front portion is not damage, but a bit of interrupted growth. The termination is undamaged, and the only roughness is on the back which cannot be seen when the piece is displayed. It very much resembles a classic Elmwood Calcite, though notably without color. A fantastic example of this historic, important and very hard to find Calcite crystals. Please note: The label accompanying this piece states that the crystal fluoresces a pale red hue, but we couldn't see much fluorescence under either SW or LW UV light. Valued at $800. Ex Kay Robertson Collection (#5322). Kay was a prominent California collector, who specialized in European classics. She nearly lived 100 years from April 1920 - March 2020. See the article in the March-April, 2007 Mineralogical Record ( https://www.mineralogicalrecord.com/pdfs/Kay%20Robertson%20Collection.pdf ), and the 50+ page article in the German Magazine "Mineralien Welt" November-December 2017.