Sanidine (GEM) (ex Richard A. Kosnar Collection)

Item Description

For a long time the crystals from this locality were labeled as being Orthoclase, but I think every piece that's been tested has proven that they're all Sanidine. With that said, they are some of the most iconic crystals of Feldspar in the world as they are GEM quality (a great rarity for Feldspar) and beautifully colored. Itrongay has been known for around 100 years producing these specimens. The yellow color of the crystals is actually caused by iron content, which can replace aluminum in the space cell of the Sanidine molecules. This piece is a classic specimen of this beloved material dating back to the 1960s featuring fine blocky monoclinic form, sharp lustrous faces and WATER CLEAR clarity with that fine soft yellow color. The specimen comes from the collection of Richard Kosnar (the namesake for Kosnarite) and actually sat on his desk for nearly 40 years until he passed in 2007.