[ Top ] [ Japanese ]

Paragonite [abbr. Pg ]

Year of discovery: 1843 (Sponda Alp - Pizzo Forno, Switzerland), 1931 (Japan)

Locality list: 49 localities of paragonite

• NaAl₂AlSi₃O₁₀(OH)₂
• [Na⁺][Al³⁺₂][(OH)₂|AlSi₃O₁₀]^7-

• Class: Dioctahedral < True mica group < Mica supergroup
• Class: Phyllo-Aluminosilicate - Hydroxide
• Insoluble in: HCl
• Electrical: Electrostatic (Rubbed, Positive)
• Substitution pseudomorph: Replace Cordierite and Indialite. (Cerasite)
• Substitution pseudomorph: Replace Marialite.

• Na => Cs: Nanpingite
• Na => K: Muscovite (Series)
• Na => NH₄: Tobelite

• Color: White, Pale yellow
• Streak: White
• Luster: Pearly
• Diaphaneity: Transparent-Translucent

• Habit: Hexagonal platy

• Cleavage: Perfect on {001} (1 plane)
• Hardness: 2.5
• Density: 2.8

• System: Monoclinic (1M, 2M₁), Triclinic (3T) (Layer-stacking polytype)
• Group: 2/m, C2/c
• Lattice: a=5.1, b=8.9, c=19.3, β=95.0