Beautiful specimen of sharp Sphalerite tetrahedrons with Calcite from the famous Madan ore field, Bulgaria. The black Sphalerite tetrahedrons have strong luster. The crystals show penetration twinning. They are chunky, sharp, well isolated and shiny. The tips are truncated. Come colorless Calcite is seen too. In good condition – one damage. On acrylic base.

Fantastic!