Dioptase (classic material)

Item Description

The Tsumeb Mine (as of the time of this posting), has produced 348 different mineral species, making it one of the most prolific localities in history. With that said, one of the signature species from this mine is Dioptase. The words Tsumeb and Dioptase are almost impossible to separate in the mineral world, as this mine produced undoubtedly the finest pieces of Dioptase ever seen. The superior color and quality of the best Tsumeb Dioptase crystals just stands above Dioptase from any other mine. Dioptase is a beloved copper silicate, celebrated for having one of the most desirable and well-known green hues in the world. Most of the Tsumeb Dioptase specimens were mined over 50 years ago, and good ones are not nearly as easy to find on the market these days. The crystals on this specimen exhibit a beautiful strong emerald green color (impossible to replicate in photos or a video) which made these specimens so famous, and they GLOW with color when backlit. The crystals measure up to about 8 mm and feature very sharp, highly lustrous, very well-formed faces with an excellent textbook trigonal shape, sitting on minor matrix The crystals themselves are in good condition overall and look beautiful up close. The piece sits beautifully on its own without the aid of a base or clay.
Valued $2,000.
This piece comes from the personal collection of recently deceased Colorado mining legend, Dave Bergman (1939-2025), the maternal grandfather of Brian Kosnar. Dave is now retired from mining, but he worked for decades in various mines underground in Colorado, as a miner, mechanic, engineer, shift boss and foreman. His biggest claim to fame is that he was the foreman and the primary person in charge of mining and specimen recovery at the Sweet Home Mine in Colorado in the 1970s alongside his son-in-law, Rich Kosnar. This project what was the FIRST ever operation for specimen recovery at this historic locality. A full-page photograph of Dave can be seen mining underground at the Sweet Home in on page 58 of Peter Bancroft's book "Gem and Crystal Treasures".