Stilbeenit
Stilbenite is a rare mineral with the chemical formula Pb₉Sb₂₂S₄₂. It is a lead antimony sulfide. Stilbenite crystallizes in the triclinic system and typically forms as fine-grained aggregates or massive material. It is known for its distinctive metallic luster and a dark gray to black color. The mineral was first described in 1911 from a specimen found in the San Antonio mine in Santa Eulalia, Chihuahua, Mexico. The name "stilbenite" is derived from the Greek word "stilbein," meaning to glitter or shine, referring to its metallic appearance.
Stilbenite is a member of the complex sulfosalt mineral group. Its formation is generally associated with hydrothermal