Natural Quartz Cluster with Galena and Sphalerite Crystals from Bulgaria 337g

Two halves with two very different characters. The upper part is a dense growth of fine quartz needles, colorless to milky, standing in radiating starbursts and small sprays over a pale grey-green ground, with rusty iron staining showing between them. Below the boundary the piece turns dark: black sphalerite and a tight group of galena crystals with sharp faces and bright metallic surfaces, clean and well formed, with brassy pyrite specks scattered around them. The line between the two is sharp, and that contrast is the appeal of the piece.

Needle quartz of this kind grows late, over the sulfides, which is why it sits on top of the galena and sphalerite rather than under them. From the Bulgarian lead-zinc field in the Rhodope Mountains. Untreated. Galena is 2.5 on the Mohs scale, sphalerite 3.5 to 4 and quartz 7, and the fine needles are the delicate part. At 337g and 100mm it is a well-sized shelf specimen.

Natural quartz with galena and sphalerite, Bulgaria, single piece.