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Microcline [abbr. Mc ]

Year of discovery: 1830 (Arendal, Norway, and Stavern (Fredriksvärn), Norway), 1885 (Japan)

Locality list: 283 localities of microcline

• KAlSi₈O₈
• [K⁺][AlSi₃O₈]^-
• Si-Al is ordered. Formed below 300 degree.

• Class: Alkaline feldspar subgroup - Feldspar group
• Class: Tecto-Aluminosilicate
• Variety: Amazonite (+Pb, Green)
• Insoluble in: HCl
• Fluorescence: Short UV excitation (Blue, Dark red, Pegmatite samples)
• Radioactive: Very weak

• Polymorph: Orthoclase (Monoclinic, Formed between 300-650 degree, Intermediately ordered Si-Al)
• Polymorph: Adularia (Monoclinic, Formed between 300-650 degree, Intermediately ordered Si-Al, Rhombic)
• Polymorph: Sanidine (Monoclinic, Formed above 650 degree, disordered Si-Al)

• K => (Na,K): Anorthoclase
• K => Rb: Rubicline
• K => Na: Albite, Kumdykolite, Lingunite

• KSi => CaAl: Anorthite, Dmisteinbergite, Svyatoslavite
• KSi => BaAl : Celsian, Paracelsian
• KSi => SrAl: Slawsonite

• Color: White, Pale blue
• Streak: White
• Luster: Vitreous
• Diaphaneity: Transparent-Translucent

• Habit: Thick Tabular

• Cleavage: Perfect on {001} (1 plane), Good on {010} (1 plane)
• Hardness: 6-6.5
• Density: 2.6

• System: Triclinic
• Group: (-1), C(-1)
• Lattice: a=8.6, b=13.0, c=7.2, α=90.3, β=116.1, γ=89.0