Natural Cleiophane Green Sphalerite with Quartz Cluster Crystal from Bulgaria 51g

A wedge of white quartz, chalky and crusted with fine crystal, with the interest concentrated along its top edge. Two cleiophane crystals sit there side by side: the larger is rounded and multi-faced, in olive to grey-green with a glassy sheen, and the smaller beside it is lighter and more yellow-green, with clearly stepped faces. Below them the quartz runs white and even, broken only by a few tiny galena crystals.

The green in cleiophane comes from having very little iron in the sphalerite structure; the more iron, the blacker the crystal. Set against white quartz, the color shows more readily than it would on a dark matrix. Bulgaria's Rhodope lead-zinc mines produce cleiophane in this habit regularly. Untreated. Sphalerite is 3.5 to 4 on the Mohs scale and quartz 7. At 54mm it is a small, tidy specimen that suits a tray or a shelf.

Natural cleiophane green sphalerite with quartz, Bulgaria, single piece.