Natural Sphalerite Cluster Crystal from Bulgaria 37g

A rounded, compact cluster built from tightly packed sphalerite crystals, dark grey-black with sharply striated faces that step across one another in a mosaic. Warm amber-brown shows through wherever a crystal is thin enough to pass light, and rust-orange iron staining picks out several of the hollows. A mossy green film of chlorite has grown over parts of the surface, and the mix of green, rust and near-black gives the piece a weathered, straight-from-the-vein look.

Sphalerite is zinc sulfide, and the striations running across these faces are growth lines rather than damage, a normal feature of well-formed crystals. The chlorite coating is a companion mineral from the same vein system in the Rhodope Mountains of Bulgaria. Untreated. At 3.5 to 4 on the Mohs scale it is soft, and the compact 49mm size makes it easy to keep in a drawer or on a small shelf.

Natural sphalerite cluster, Bulgaria, single piece.