Cassiterite (gemmy cyclic twins)

Item Description

Some of the most iconic and beautiful crystallized examples of Cassiterite in the world are those from the famed Viloco Mine in Bolivia. There are many tin deposits throughout the Cordillera Real of this country, and it's important to note that the majority of most of the tin found in Bolivia is in the form of Cassiterite, but a large percentage of that material is massive and uncrystallized, and not collector quality. Viloco stands out as producing not only the finest crystallized pieces, but it's the only mine to yield transparent/gemmy Cassiterites anywhere in Bolivia! This miniature sized specimen hosts excellent quality, very sharp, highly lustrous, cyclic twinned crystals of Cassiterite sitting on white Quartz matrix. What really sets this piece apart is the fact that the Cassiterite crystals are GEMMY, when backlit showing a rich golden-amber hue. The piece is in excellent shape on the front/display side, but there are some contacted areas on the back where it was removed from the pocket wall. The largest twin measures 2.7 cm across. These classic specimens from Viloco are simply not seen for sale in today's market, so if you're in the market for a good quality example of this classic material, don't pass this one up for a great price. Valued at $3,000. This piece comes from the personal collection of Colorado mining legend, Dave Bergman, 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".