Tetrahedrite ps. Azurite with Galena

Item Description

Tetrahedrite from Tsumeb are regarded among the finest in the world, and this very interesting small-cabinet piece brings a lot to the table as you consider its unusual shape. Perched perfectly near the top of the specimen is a sharp and highly distinctive, 4 cm 'fan' of Tetrahedrite crystals. Dramatic in its presentation, yet with such a different habit, this is undoubtedly one of the well-known and rare Tetrahedrite pseudomorphs (replacements) after azurite crystals. More likely, it is a replacement of malachite after azurite, for this locale. Pseudomorphs, period, are always interesting in light of the usually complex chemical substitutions at play, and there remains some amount of discussion for these as to whether the original crystals were Chalcocite or Azurite, as once thought (most people seem to agree such forms are indeed after azurite). The majority of the specimen consists of a three-dimensional array of Tetrahedrite tetrahedra, modified to a large extent, possibly by the cube. This creates an almost curved look to many of the crystals, and they have for the most part an appealing, silvery matte finish. A few faces do have bright shiny luster. Tucked in among these are numerous cubic Galenas with a shiny, bright metallic luster that helps them peek out among all the Tetrahedrites. Possibly older material from this renowned locality, the Tetrahedrites were known for being a very rich copper ore with many specimens ending up in the ore crusher, so we are thankful that this fine and unique crystalline specimen survived. Note that most older labels identified this as tennantite in many cases.