Kozoite

minerals

lanthanite

kimuraite

lokkaite

Formulae:
Kozoite-(La): La(CO3)(OH)
Kozoite-(Nd): Nd(CO3)(OH)
Carbonates, ancylite group
Specific gravity:
kozoite-(La) 4.16 calculated
kozoite-(Nd) 4.77 calculated
Streak, kozoite-(La): La White
Colour:
kozoite-(La) pink, yellow, white
kozoite-(Nd) pale pinkish-purple to white
Environments

Hydrothermal environments

Kozoite-(La) is a rare secondary mineral in fractures in alkali olivine basalt, probably of hydrothermal origin, associated with kozoite-(Nd), lanthanite-(Nd) and kimuraite-(Nd) (HOM, Webmin ).

Kozoite-(Nd) is formed by post magmatic hydrothermal activity in an alkali olivine basalt from the last-stage lava of a volcanic sequence; it is probably a dehydration product of lanthanite-(Nd) (Webmin).

Localities

Kozoite-(La): The type locality is Mitsukoshi, Hizen-cho, Karatsu City, Saga Prefecture, Japan, where it occurs in olivine basalt associated with lanthanite-(Nd), kozoite-(Nd), kimuraite-(Y), lokkaite-(Y), calcite, aragonite and opal variety hyalite (Minrec 35.4.354, Mindat).

Kozoite-(Nd): The type locality is Niikoba, Hizen-cho, Karatsu City, Saga Prefecture, Japan, where it occurs in olivine basalt associated with lanthanite-(Nd) and kimuraite-(Y) (AM 85.1076-1081)

Common impurities:
Kozoite-(La): Nd
Kozoite-(Nd): La,Sm,Pr

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