Sphalerite (rare locality stone)

Big Four Mine, Summit County, Colorado, USA
Gems, 1.21 ct ; 7.78 mm x 5.58 mm
Start Time: 10/07/2021 9:00:00 pm (CDT)
End Time: 10/14/2021 7:00:00 pm (CDT)
Auction Closed

Item Description

On a worldwide level, gem grade Sphalerite is not common. Keep in mind that Sphalerite is a sulfide, and most sulfide species are always opaque. Sphalerite from Colorado is rarely seen in faceted gems, as the majority of mines produced only opaque black material. The lesser known Big Four Mine in Summit County was the source of some of the best gem grade Sphalerite from any mine in Colorado, producing stones that ranged from deep orange and brown hues to yellows, and highly sought after GREEN stones! In the early 2000s a small discovery was made of gem grade Sphalerite on the dumps of the Big Four Mine in Colorado. This gem was only recently faceted from a stash of rough that we found in an old collection. This "Oval Brilliant" cut gem has a gorgeous green hue with a very slight golden-yellow overtone. The stone is only very slightly included which is common from this locality, as it's almost impossible to find a stone over 1 carat that is completely clean.

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