Ilsemannite (ex Rich Kosnar Collection)

Item Description

A very rich sample of fine blue/white Ilsemannite on matrix from the famous Mogul Tunnel in Boulder County, Colorado. I took the liberty of photographing these bladed crystals under the microscope for a better "up close" view. There is some question as to whether or not this Molybdenum oxide is a valid species, but I cannot find anything in the current literature to say whether or not it is valid or discredited. Nonetheless, specimens of this material are not seen on the market in any quantity, and this is certainly one of the finest pieces that I know of from Boulder County. The piece was valued in Rich Kosnar's collection catalogue at $600, and I strongly believe that value holds up today, and may actually be worth more to a Colorado or rare species collector.