Prehnite finger cast after Anhydrite Ferberite Ahlfeld worked the San Jose

Ahlfeld worked the San Jose mine and Itos mine (the other significant Andorite locality at the same mountain in Oruro) when the mines were used predominantly as a major source of tin to the United States during WWII

this is also a great opportunity to obtain a good-sized single crystal of a species that is often only found in crude or microscopic crystals

but you don’t see pieces like this anymore

Specimen #VIVBOL81813

and this beautiful multicolored gem crystal is no exception

Prehnite finger cast after Anhydrite Ferberite Ahlfeld worked the San JoseA representative specimen of Prehnite fingers after Anhydrite with a darker green color, and a coating of a secondary clay mineral. Overall, the piece is actually in good condition, with a predominant finger flaring out of the center of the piece. The color in the photos is accentuated by the lighting we used to photograph the piece, but it is a bit more muted in person. The Prospect Park Quarry is arguably the most famous mineral producing basalt