Mineral - Ernstite
Ernstite
Chemical Properties
Mineral Class
Phosphates
Toxicity
none
Formula
(Mn²⁺,Fe³⁺)Al(PO₄)(OH,O)₂ · H₂O
Unit Cell
a=13,32 b=10,50 c=6,70 β=91° Z=8
Physical Properties
Hardness
3 - 3.5
Streak
white
Density
Normal (2-3,5)
Cleavage
Fracture
nd
Tenacity
Brittle
Optical Properties
Color
brownorangeyellow
Birefringence
Luster
Vitreous,
Greasy,
Pearly
Transparency
translucent
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
Space Group
Habit
blocky, prismatic, tabular
Formation
Sekundär, durch Verwitterung von Eosphorit
Paragenesis
Twinning
Rarity
Rather rare
Synonyms
Ernstite
Composition
Elements
Mass
P₂O₅
29,85
Al₂O₃
24,34
Fe₂O₃
11,84
FeO
0,43
MnO
17,84
MgO
1,00
CaO
0,85
H₂O
13,85
Namibia