Mineral Species: Topaz var. Pyknite

Chemical Formula: Al2(SiO4)(OH,F)2

Chemical Name: Aluminium Fluorosilicate

Mineral Class: Nesosilicate

Mineral Notes: Topaz is a relatively rare Silicate closely related to the Olivine group. It is found in granites, particulalry pegmatites, and is usually associated with Beryl and Tourmaline. Transparent Topaz is often used as a gemstone being hard, durable and having a high refractive index. Brown Topaz usually turns pink on heating, and thus most of the pink stones found in jewelery have been heat treated. Pyknite is a dense variety of Topaz, hence the name, after the greek Pyknos, meaning dense.

Description: The specimen consists of columnar crystals of cream and pink Topaz interspersed with a matrix of Biotite. The combination is very aesthetic and considered a mineral "classic". Pyknite in this form is only found in one worldwide location making it very rare and thus sought after by many collectors.  

Location: Altenberg, Erzegebirge, Germany.