[ Top ] [ Japanese ]

Ferro-richterite [abbr. Frct ]

Year of discovery: 1946 (World), 1964 (Japan)

Locality list: 2 localities of ferro-richterite

• Na₂CaFe₅Si₈O₂₂(OH)₂
• Na₂Ca(Fe,Mg)₅Si₈O₂₂(OH)₂
• [Na⁺][Ca²⁺][Na⁺][Fe²⁺₅][(OH)₂|(Si₄O₁₁)₂]^14-

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

• Na₂ => Ca: Ferro-actinolite

• Fe => Mg: Richterite (Series)

• NaFe => []Al: Ferro-winchite
• NaFe²⁺ => []Fe³⁺: Ferro-ferri-winchite

• NaSi => CaAl: Ferro-edenite

• FeSi => Al₂: Ferro-katophorite
• Fe²⁺Si => Fe³⁺Al: Ferro-ferri-katophorite

• Fe₂Si₂ => Al₄: Ferro-taramite

• Color: Reddish brown, Dark green
• Luster: Vitreous
• Diaphaneity: Transparent-Translucent

• Cleavage: Perfect on {110} (2 planes)
• Hardness: 5-6
• Density: 3.5

• System: Monoclinic
• Group: 2/m, C2/m
• Lattice: a=10.0, b=18.2, c=5.3, β=103.7