Formula: (Na,K)(Mg,Fe,Al)6(Si,Al)8O20(OH,F)4
Origin of name: for David R. Wones (1932-1984), Professor of Geology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
Crystal system: Monoclinic
Crystal class: 2/m
Twinning: Twin axis {310| and composition plane {001} common
Unit cell: a = 5.312, b = 9.163, c = 9.825, β = 103.18°
Colour: Pale to dark brown, yellow brown
Diaphaneity: Transparent to translucent
Luster: Vitreous
Habit: irregular basal cleavage plates, twinned
Hardness: 2.5 to 3
Specific gravity: 2.89
Cleavage: 1; {001} perfect
Tenacity: Micaceous fracture, elastic
Streak: White
Synonyms/varieties: Natriumphlogopite,
sodiumphlogopite
Comments: member of mica-group, -1M polytype is known
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