Hydrobiotite

hydrobiotite

vermiculite

biotite

zircon

Images

Formula: K(Mg,Fe²⁺)₆(Si,Al)₈O₂₀(OH)₄.nH₂O
Phyllosilicate (sheet silicate), mica group
Crystal System: Monoclinic
Specific gravity: 2.49 to 2.64 measured
Hardness: 2½ to 3
Streak: White
Colour: Blackish, brownish, golden yellow, pinkish
Common impurities: Ti,Cr,Mn,Ca,Sr,Ba,Na,Rb,F,P
Environments: Near-surface hydration of prior minerals (Mindat).
Well-ordered hydrobiotite consists of a regular alternation of biotite and vermiculite layers (AM 68.420-425).
It occurs as an alteration product of other micas, associated with vermiculite, biotite, apatite and zircon (HOM).

Localities

Hydrobiotite is common worldwide, found in a variety of sedimentary environments (Webmin).

Back to Minerals