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Böhmite, Bohmite [abbr. Bhm ]

Year of discovery: 1927 (Mas Rouge, France), 1950 (Japan)

Locality list: 27 localities of böhmite

• γ-AlO(OH)
• [Al³⁺][OH|O]^3-

• Class: Böhmite (Bohmite) group
• Class: Oxide - Hydroxide

• Polymorph: Diaspore (α, Orthorhombic)

• Al => Fe: Goethite (α), Akaganeite (β), Lepidocrocite (γ), Feroxyhyte (δ)
• Al => Mn: Groutite (α), Feitknechtite (β), Manganite (γ)
• Al => V: Montroseite
• Al => Cr: Guyanaite, Bracewellite
• Al => Ga: Tsumgallite
• Al => Co: Heterogenite

• Color: White, Pale yellow, Yellowish green
• Streak: White
• Luster: Vitreous
• Diaphaneity: Translucent

• Cleavage: Perfect on {010} (1 plane), Good on {100} (1 plane), Poor on {001} (1 plane)
• Hardness: 3.5
• Density: 3.0

• System: Orthorhomic
• Group: mmm, Amam
• Lattice: a=3.7, b=12.2, c=2.9

Synonym: Boehmite