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Magnesiofoitite (Photo)

Year of discovery: 1994 (Japan as the first occurence in the World)

Locality list: 5 localities of magnesiofoitite

• Mg₂Al₇Si₆O₁₈(BO₃)₃(OH)₄
• ([],Na)Mg₂(Al,Fe)Al₆Si₆O₁₈(BO₃)₃(OH)₄
• [][Mg²⁺₂][Al³⁺][Al³⁺₆][(OH)₄|(BO₃)₃|(SiO₃)₆]^25-

• Class: Vacant-subgroup 1 < X-vacant-tourmaline group < Tourmaline supergroup
• Class: Cyclosilicate (Single ring) - Borate - Hydroxide
• Electrical: Piezoelectric, Pyroelectric

• []Al => NaMg: Dravite

• Mg => Fe: Foitite

• Mg₂Al => LiAl₂: Rossmanite

• Color: Pale bluish gray
• Streak: White
• Luster: Earthy
• Diaphaneity: Transparent

• Habit: Acicular

• Cleavage: No
• Hardness: 7

• System: Trigonal
• Group: 3m, R3m
• Lattice: a=15.9, c=7.2