Mineral - Picromerite
Picromerite
Chemical Properties
Mineral Class
Sulphates
Toxicity
none
Formula
K₂Mg(SO₄)₂ · 6H₂O
Unit Cell
a=9,66 b=8,80 c=5,29 β=107° Z=4
Physical Properties
Hardness
2.5
Streak
white
Density
Normal (2-3,5)
Cleavage
Auf (201) perfekt
Fracture
Tenacity
Optical Properties
Color
whitegraycolorless
Birefringence
Luster
Vitreous,
Earthy
Transparency
translucent,
transparent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
Space Group
Habit
blocky, coarse, massive, prismatic, Rhombohedron, columnar, tabular
Formation
Evaporit, Sedimentär, Vulkanisch in Fumarolen
Paragenesis
Twinning
Rarity
Rarely
Synonyms
Picromerite
Composition
Elements
Mass
SO₃
30,74
MgO
10,40
K₂O
23,28
Cl
0,28
H₂O
26,87
Deutschland
Groups and Members
Picromerit-Gruppe