important Koettigite ex. Belsky Coll.

Item Description

Koettigite is hydrated zinc arsenate and this very fine rarity is from Mina Ojuela, known for the best examples of the species. The egg-shaped, oval vug is totally lined with lustrous, bluish-gray, parallel-growth, crystal clusters. THESE CRYSTALS ARE EXTREMELY ROBUST FOR THE SPECIES, AND SHOW STEREOTYPICAL CRYSTAL HABIT. Koettigite is hydraged zinc arsenate hydrate and parasymplesite is hydrated iron arsenate, and because they have such a similar appearance they can only be distinguished by chemical analysis in a lab. There is an interesting discussion of this series in the Min. Record, V. 7, #4, p. 186. In any case, it is probably the koettigite and its an outstandingly good one. Old material not found in over 30 years and there will not be more as these levels of the mine are flooded. Ex Howard Belsky Collection. Valued $800-1000. If you know the material, and you think about how many fibrous and poorly terminated ones you have seen, how few good matrix pieces, etc...then this looks like a bargain, I would think.