Abswurmbachite

Abswurmbachite is a copper manganese silicate mineral  ((Cu,Mn 2+ )Mn 3+ 6 O 8 SiO 4 ). It was first described in 1991 and named after Irmgard Abs-Wurmbach (born 1938), a German mineralogist. It crystallizes in the tetragonal system. Its Mohs scale rating is 6.5 and a specific gravity of 4.96. It has a metallic luster and its color is jet black, with light brown streaks.