Biotite
Properties
Formula | K(Mg,Fe)3AlSi3O10(OH,F)2 |
Abbreviation | Bt |
Classification | Mica |
Members | Siderophyllite, Fluorophlogopite, Annite, Tetraferriphlogopite, Phlogopite, Fluorotetraferriphlogopite, Fluorannite, Tetraferriannite, Oxyphlogopite, Eastonite |
IMA Status | Approved group |
Search other databases | webmineral.com, mindat.org, rruf.info, mineralienatlas.de, Handbook of Mineralogy, American Mineralogist Crystal Structure Database |
Crystal symmetry | Monoclinic, Point group 2/m, Space group C2/m (#12) |
Tags | Hydroxide , Subgroup, Aluminosilicate |
Composition
Element | Wt% |
---|---|
H | 0.41 |
K | 9.02 |
Mg | 14.02 |
Fe | 6.44 |
Al | 6.22 |
Si | 19.44 |
O | 43.36 |
F | 1.1 |
Total: | 100.01 |