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Pargasite [abbr. Prg ]

Year of discovery: 1814 (Pargas (Parainen), Finland), 1934 (Japan)

Locality list: 119 localities of pargasite

• NaCa₂Mg₄Al₃Si₆O₂₂(OH)₂
• NaCa₂(Mg,Fe)₄Al₃Si₆O₂₂(OH)₂
• [Na⁺][Ca²⁺₂][Mg²⁺₄][Al³⁺][(OH)₂|(AlSi₃O₁₁)₂]^16-

• Class: Ca amphibole subgroup < w(OH,F,Cl)-dominant amphibole group < Amphibole supergroup
• Class: Ino-Aluminosilicate (Double chain) - Hydroxide

• Na => K: Potassic-pargasite

• Mg => Fe: Ferropargasite (Series)

• Al => Cr: Chromio-pargasite
• Al => Fe: Magnesio-hastingsite (Series)

• NaMg => []Al: Tschermakite

• NaAl => []Si: Magnesio-hornblende

• CaMg => NaAl: Taramite

• Al₂ => MgSi: Edenite (Series)

• MgSi => Al₂: Sadanagaite

• Mg(OH)₂ => TiO₂: Kaersutite

• Color: Pale brown, Greenish brown, Dark green
• Streak: Pale grayish green, Pale greenish brown
• Luster: Vitreous
• Diaphaneity: Transparent-Translucent

• Habit: Fibrous, Prismatic

• Cleavage: Perfect on {110} (2 planes, 120 degree)
• Hardness: 5-6
• Density: 3.1

• System: Monoclinic
• Group: 2/m, C2/m
• Lattice: a=9.9, b=18.0, c=5.3, β=105.4