This article is about the mineral, for the religious sect see Adamites.

Adamite
Yellow-green adamite in limonite
General
Category	Mineral
Chemical formula	Zn2AsO4OH
Identification
Color	Yellow, green, rarely white, and occasionally purple
Crystal habit	Wedge-like prisms typically in druses and radiating clusters - also smooth botryoidal masses.
Crystal system	Orthorhombic; 2/m 2/m 2/m
Cleavage	perfect in two directions
Fracture	conchoidal
Mohs Scale hardness	3.5
Luster	adamantine
Refractive index	nα=1.708 - 1.722, nβ=1.742 - 1.744, nγ=1.763 - 1.773
Streak	white to pale green
Specific gravity	4.4
Other Characteristics	Strongly fluoresces green in short and long UV light.

Adamite is a zinc arsenate hydroxide mineral, Zn₂AsO₄OH. It is a mineral that typically occurs in the oxidized or weathered zone above zinc ore occurrences. Adamite is usually yellow in color, but tints of green occur due to inclusion of copper substitutions in the mineral structure. Olivenite is a copper arsenate that is isostructural with adamite and there is considerable substitution between zinc and copper resulting in an intermediate called cuproadamite. Manganese, cobalt, and nickel also substitute in the structure. An analogous zinc phosphate, tarbuttite, is known.

The yellow to bright lime-green colored crystals and druze along with its distinctive fluorescence make adamite a favorite among mineral collectors. Found in Mapimi, Mexico; Greece; and California and Utah in the United States.

Adamite was named after the French mineralogist Gilbert Joseph Adam (1795-1881). The type locality is in the Atacama Desert in Chile.

Adamite from Mexico

See also

• A list of minerals with associated Wikipedia articles
• A comprehensive list of minerals
• List of minerals named after people

References

• Mindat.org
• Webmineral.com
• Mineral galleries

Source: adapted by the editor from Wikipedia, the free encyclopedia; from the article "Adamite". Image Credit.

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