Mineral - Antigorite
Antigorite
Chemical Properties
Mineral Class
Silicates
Toxicity
high
Formula
Mg₃(Si₂O₅)(OH)₄
Unit Cell
a=43.53 b=9.26 c=7.26 β=91° Z=16
Physical Properties
Hardness
2.5 - 3.5
Streak
white
Density
Normal (2-3,5)
Cleavage
Perfect after {001}, indistinct after {100} and {010}
Fracture
fibrous,
splintery
Tenacity
Elastic-flexible
Optical Properties
Color
whitegreen
Birefringence
0.005
Luster
Greasy,
Silky,
Resinous
Transparency
translucent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
monoclinic-domatic - m
Space Group
Cm (8)
Habit
leafy, fibrous, felted, massive, tabular
Formation
Through metasomatism of ultramafic igneous rocks
Paragenesis
Twinning
Rarity
Common
Synonyms
Antigorite
Composition
Elements
Mass
SiO₂
41.65
Al₂O₃
0.10
Fe₂O₃
2.88
FeO
0.16
MnO
0.05
MgO
41.06
H₂O
14.22
Scotland (Dana 1892)
Groups and Members
Kaolinite-Serpentine-Group
Serpentine-Subgroup
Name and first record : Named after its type locality in the Antigorio Valley, Italy. First described in 1840.
Chemistry :
Synonyms : Asbestos, Baltimorite, Gymnite, Porcellophite, Protoantigorite, Septeantigorite, Thermophyllite, Zermattite, Jade
Varieties : Al-Antigorite, Bowenite, Jenkinsite, Vorhauserite, Webskyite, Williamsite
Abbreviation : Atg
literature
Dana, J. D., & Dana, E. S. (1892). The system of mineralogy of James Dwight Dana, 1837-1868: descriptive mineralogy . J. Wiley & sons.