Mineral - Oripigment
Oripigment
Chemical Properties
Mineral Class
Sulfides and sulfosalts
Toxicity
high
Formula
As₂S₃
Unit Cell
a=11.48 b=9.58 c=4.26 β=90.41° Z=4
Physical Properties
Hardness
1.5 - 2
Streak
yellowgreen yellow
Density
Normal (2-3,5)
Cleavage
Perfect after {010}
Fracture
Tenacity
Brittle,
Inelastic-flexible
Optical Properties
Color
redorangeyelloworange red
Birefringence
0.620
Luster
Greasy,
Pearly
Transparency
translucent,
transparent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
Space Group
Habit
blocky, crusty, prismatic, Rhombohedron, tabular
Formation
In hydrothermal ore deposits
Volcanic in fumaroles
Secondary as an alteration product of realgar
Paragenesis
Twinning
Contact twins after {100}
Rarity
Common
Synonyms
Oripigment
Composition
Elements
Mass
As
60,90
S
39,10
Peru