Boleite

boleite

pseudoboleite

cumengeite

atacamite

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Formula: KAg9Pb26Cu24Cl62(OH)48
Hydroxyhalide, silver-bearing mineral, commonly surficially layered with or overgrown by the epitaxial minerals cumengeite or pseudoboleite, mutually parallel to {001} (Mindat).
Specific gravity: 5.054 measured, 5.062 calculated
Hardness: 3 to 3½
Streak: Blue, with greenish tint
Colour: Deep prussian blue to indigo; bluish green in transmitted light
Solubility: Soluble in nitric acid
Environments

Hydrothermal environments

Boleite is a secondary mineral formed through reaction of chloride with primary sulphides in the oxidised zone of sedimentary lead-copper deposits; in smelter slag immersed in and leached by sea water (HOM).

Localities

At the type locality, the Boleo District, Santa Rosalía, Mulegé Municipality, Baja California Sur, Mexico, boleite occurs in white clay in the oxidised zone of a lead-copper deposit, formed through reaction of chloride with primary sulphides. Associated minerals include pseudoboleite, cumengeite, atacamite, paratacamite, anglesite, cerussite, phosgenite and gypsum (HOM, Dana).

At the Mammoth-Saint Anthony mine, St. Anthony deposit, Tiger, Mammoth Mining District, Pinal county, Arizona, USA, boleite was found in the foundations of an old silver mill, the result of chemical spills in the mill (Dana). Associated minerals include pseudoboleite, anglesite, cerussite, atacamite, paratacamite, leadhillite, paralaurionite, caledonite, phosgenite, matlockite and bideauxite (HOM).

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