Minerals : Phyllosilicates - Biotite, Muscovite, Lepidolite, Chlorite

Luster - vitreous
Streak - white, very pale brown (biotite)
Hardness - 3-4
Density - moderately low
Cleavage - perfect 1 direction, parallel sheets
Color - variable, black (biotite), white (muscovite), pink/lavender (lepidolite), green (chlorite)
Crystal system - monoclinic
Crystal form/habit - sheets, books, pseudo-hexagonal
Extra notes - we mainly use color to distinguish

Видео Minerals : Phyllosilicates - Biotite, Muscovite, Lepidolite, Chlorite канала GLG 321 Mineralogy