[ Top ] [ Japanese ]

Glaucodot

Year of discovery: 1849 (Huasco, Chile), 1933 (Japan)

Locality list: 12 localities of glaucodot

• Co_0.5Fe_0.5AsS
• (Co,Fe)AsS
• [Co²⁺_0.5Fe²⁺_0.5][As³⁺][S]

• Class: Sulfide
• Soluble in: HNO₃

• Co₂Fe₂ => Co₃Fe: Alloclasite (Polymorph?)

• Co_0.5Fe_0.5 => Fe: Arsenopyrite
• Co_0.5Fe_0.5 => Co: Cobaltite

• Color: Grayish-Reddish silver
• Streak: Black
• Luster: Metallic
• Diaphaneity: Opaque

• Habit: Prismatic elongated to [001] or [010]
• Striation: [001]
• Twin: {101} and {012} cross twin or triple twin

• Cleavage: Perfect on {010} (1 plane), Good on {101} (2 plane)
• Hardness: 5
• Density: 6.1

• System: Orthorhombic
• Group: mm2, Pmn2₁
• Lattice: a=14.2, b=5.6, c=3.3

Etymology: Blue in Greek, as Co of this mineral was used for coloring glass to blue.