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Oxy-foitite

Year of discovery: 2016 (Cooma metamorphic complex, Australia)

Locality list:

• FeAl₂Al₆Si₆O₁₈(BO₃)₃O(OH)₃
• [][Fe²⁺][Al³⁺₂][Al³⁺₆][(OH)₃|O|(BO₃)₃|(SiO₃)₆]^26-

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

• Fe => LiAl: Oxy-rossmanite

• AlO => Fe(OH): Foitite

• Color: Black
• Streak: Grayish white
• Luster: Vitreous
• Diaphaneity: Transparent-Translucent

• Cleavage: No
• Hardness: 7
• Density: 3.2

• System: Trigonal
• Group: (-3)m, R(-3)m
• Lattice: a=16.0, c=7.2