Sampleite

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Formula: NaCaCu₅(PO₄)₄Cl.5H₂O
Hydrated phosphate containing halogen, lavendulan group, forms a series with lavendulan
Crystal System: Orthorhombic
Specific gravity: 3.2 measured, 3.26 calculated
Hardness: 4
Streak: Light blue
Colour: Light blue, bluish green; blue in transmitted light
Solubility: Readily soluble in acids
Environments:

Pegmatites
Hydrothermal environments
Cave deposits

Sampleite occurs in the oxidised zones of copper deposits in arid climates, in caves derived from copper sulfides in cave walls and phosphorus from bat guano, in miarolytic cavities in granite and in pegmatites (Mindat). Associated minerals include atacamite, libethenite, pseudomalachite, torbernite, chrysocolla, gypsum, calcite and jarosite (HOM).

Localities

At Endeavour 22 (Northparkes Mine), Goonumbla, Kennedy county, New South Wales, Australia, world class specimens of sampleite have been collected scattered across the fracture faces of quartz monzonite. Occasionally atacamite and libethenite occur on the same specimen. Some specimens have brilliant blue sampleite perched on reddish orange coatings of goethite (AJM 10.2.55).

At the Kintore opencut, Broken Hill South Mine, Broken Hill, Broken Hill district, Yancowinna county, New South Wales, Australia, sampleite occurs with hemimorphite and libethenite, or with pyromorphite and libethenite, or as coatings on cerussite with linarite and jarosite in quartz-rich rocks (AJM 3.1.51).

At the Jingemia Cave, Moora Shire, Western Australia, sampleite occurs as a reaction of CuS with guano, and associated with atacamite, weddellite, gypsum, goethite, manganese oxides, birnessite, dolomite, halite, apatite and malachite (Dana).

At the Mantos Blancos Mine, Antofagasta, Antofagasta Province, Antofagasta, Chile sampleite occurs in highly oxidised ore with atacamite, calcite, halite and chrysocolla (Dana).

At the type locality, the Chuquicamata mine, Chuquicamata District, Calama, El Loa Province, Antofagasta, Chile, sampleite occurs in highly oxidised ore associated with gypsum, atacamite, jarosite, limonite and libethenite (AM 27.586-589, Mindat, Dana). Also commonly associated with dendrites of manganese and iron oxides, gypsum, specular hematite and libethenite in sericitised and kaolinised quartz monzonite and granodiorite, or associated with limonite and atacamite in quartz monzonite. In all the occurrences sampleite is present under highly oxidised near-surface conditions. It appears to be the most recent mineral deposited with the exception of gypsum (AM 27.586-589).

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