Mineral - Amblygonite
Amblygonite
Chemical Properties
Mineral Class
Phosphates
Toxicity
none
Formula
LiAl(PO₄)F
Unit Cell
a=6.64 b=7.74 c=6.91 α=91° β=117° γ=91° Z=4
Physical Properties
Hardness
5.5 - 6
Streak
white
Density
Normal (2-3,5)
Cleavage
Perfect after {100}, good after {110}, imperfect after {0 1 1} and {001}
Fracture
conchoidal,
uneven
Tenacity
Brittle
Optical Properties
Color
whiteyellow
Birefringence
0.022
Luster
Vitreous,
Greasy
Transparency
translucent,
transparent
Pleochroism
Geomineralogical Properties
Crystal System
triclinic
Point Group
triclinic-pinacoidal - 1
Space Group
P 1 (2)
Habit
massive, prismatic
Formation
Igneous, in granitic pegmatites
Paragenesis
Twinning
Contact twins
Rarity
Rather rare
Synonyms
Amblygonite
Composition
Elements
Mass
P₂O₅
48.44
Al₂O₃
33.90
Li₂O
10.12
F
18.56
Germany (Palache et al. 1952)
Groups and Members
Amblygonite-Group
Name and first discovery : Named after the Greek words "amblys" for "blunt" and "goni" for "angle," it refers to the fact that amblygonite cleaves in different directions, each at a different angle, but other than 90°. It was first described in 1817 by August Breithaupt of Saxony.
Chemistry :
Synonyms :
Varieties :
Abbreviation : Aby
literature
Palache, C., Berman, H., & Frondel, C. (1952). Dana's system of mineralogy. Geologiska Föreningen i Stockholm Förhandlingar , 74 (2), 218-219.