Vrbaite
Vrbaite | |
---|---|
Vrbaïte, Crven Dol Mine, Allchar (Alsar), Roszdan, North Macedonia | |
General | |
Category | Minerals |
Formula | Tl4Hg3Sb2As8S2 |
Strunz classification | 2 SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.) 2.H Sulfosalts of SnS Archetype Space Group C mca Point Group 2/m 2/m 2/m |
Dana classification | 03 |
Crystal system | orthorhombic |
Crystal class | Dipyramidal ; {C 2/m 2/c 2 India/a} |
Identification | |
Color | black, gray-black, bluish, dark red; on polished sections, bluish white with internal red highlights |
Fracture | uneven/irregular to conchoidal |
Tenacity | 3,5 |
Density | 5,27-5,33 |
Refractive index | n = 2,72-2,73 |
Dispersion | r > v |
Ultraviolet fluorescence | aucune |
Absorption spectra | opaque |
Vrbaite (symbol: Vrb) is an opaque to subtranslucent brittle mineral with chemical formula Tl4Hg3Sb2As8S20 and pyramidal crystals. It is names after Czech mineralogist Karel Vrba. It is bluish white with red internal reflections and dark red in translucent thin fragments. It is classified in the class "sulfides and sulfosalts".[1][2]
Type locality: Allchar deposit, Ržanovo mine, Kavadarci Municipality, North Macedonia.[2][3]