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Johnbaumite

Year of discovery: 1980 (Franklin mine, USA), 1996 (Japan)

Locality list: A locality of johnbaumite

• Ca₅(AsO₄)₃(OH)
• [Ca²⁺₅][OH|(AsO₄)₃]^10-

• Class: Apatite group - Apatite supergroup
• Class: Arsenate - Hydroxide
• Fluorescence: Short UV excitation (Orange)

• OH => F: Svabite
• OH => Cl: Turneaureite

• AsO₄ => PO₄: Hydroxylapatite, Hydroxylapatite-M

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

• Cleavage: Distinct on {1010} (3 planes)
• Hardness: 4.5
• Density: 3.7

• System: Hexagonal (H), Monoclinic (M, Fermorite)
• Group: 6/m, P6₃/m
• Lattice: a=9.7, c=6.9