Adamite Value, Price, and Jewelry Information


adamite - ojuela
Adamite: Ojuela Mine, Mapimi, Mexico (0.86). Photo © Joel E. Arem, PhD, FGA. Used with permission.

Although adamite occurs in many localities, it's very rarely cut as a gem. This mineral is much too soft and fragile for jewelry. However, collectors prize its intense fluorescence.

Adamite Value

The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.

Adamite Information

DataValue
NameAdamite
Crystallography Orthorhombic; crystals elongated or equant; druses, radial aggregates, and spheroids on matrix.
Colors Colorless; yellowish green, yellow in various shades (contains Fe); pale green, bluish green, green (contains Cu); rose and violet shades (color zoned, contains Co); purple (contains Mn).
Luster Vitreous
Fracture Subconchoidal to uneven.
Hardness 3.5
Specific Gravity 4.32-4.68 (red-violet)
Birefringence See "Identifying Characteristics" below.
Cleavage Good 1 direction.
Dispersion Strong
Luminescence Intense green in SW, LW; also lemon yellow in SW.
Transparency Translucent to transparent.
Absorption Spectrum Not diagnostic.
FormulaZn2(AsO4)OH + Co, Cu.
Pleochroism Colorless/ blue-green/yellow-green. Pale rose/ pale rose/ pale purple. Pink/ pale rose/colorless.
Optics Biaxial (+/-); 2V = 15° (Cu. Var.) to 88°. See “Identifying Characteristics” below.
EtymologyAfter Gilbert-Joseph Adam, the Parisian mineralogist who supplied the first specimens for study.
OccurrenceSecondary mineral in the oxidized zone of ore deposits.
cuprian adamite - Namibia
“Cuprian Adamite – 2009 04 19 – 4742,” Tsumeb, Namibia, on display at the Smithsonian National Museum of Natural History, by thisisbossi. Licensed under CC By-SA 2.0.

Comments

Adamite forms a series, as the zinc (Zn) analogue, with olivenite, the copper (Cu) analogue. This series has a distinct, intermediate member known as zincolivenite. (Don’t confuse olivenite with olivine).

The presence of numerous impurities can create various colors in adamites. For example, iron (Fe) can cause yellow hues. Cuprian (Cu bearing) varieties show green hues. Cobalt (Co) bearing specimens can show rose or purple/violet hues. Manganoan or manganese (Mn) bearing specimens may have purple/violet colors as well as pink and lavender.

Adamites can have an intense green fluorescence under either shortwave (SW) or longwave (LW) ultraviolet light. They may also show lemon yellow fluorescence under SW.

This specimen shows dozens of “pinwheel” adamite crystals on gossan matrix and intense neon green fluorescence. “Adamite,” Ojuela Mine, Mapimi, Durango, Mexico, 10.5 x 9.3 x 6.2 cm. © Rob Lavinsky, www.iRocks.com. Used with permission.

Identifying Characteristics

Due to wide variations in composition, optical properties can vary significantly.

Locality

α

β

γ

Birefringence

Mapimi, Mexico (reddish)

1.712

1.736

1.760

0.048

Mapimi, Mexico (rose)

1.710

1.735

1.759

0.049

Mapimi, Mexico (violet)

1.710

1.735

1.758

0.048

Mapimi, Mexico (green)

1.722

1.742

1.763

0.041

Tsumeb, Namibia (Cu)

1.742

1.768

1.773

0.031

Tsumeb, Namibia (Co)

1.722

1.738

1.761

0.039

Laurium, Greece

1.708

1.734

1.758

0.050

adamite - Greece
This cuprian specimen contains traces of cesium (Cs) as well as the rare-earth elements cerium (Ce) and dysprosium (Dy). “Adamite (cuprian and REE enriched) with Smithsonite,” Hilarion Mine, Laurium, Attiki Prefecture, Greece, 6.0 x 5.7 x 2.4 cm. © Rob Lavinsky, www.iRocks.com. Used with permission.

Synthetics

Scientists have used synthetic specimens of the adamite-olivenite series for spectroscopy research. However, there is no known jewelry use for this material.

Enhancements

None known.

Sources

The Ojuela Mine in Mapimi, Mexico produces fine sprays of crystals in limonite matrix.

Tsumeb, Namibia also produces fine crystals, sometimes colored purple by cobalt.

Laurium, Greece yields specimens often containing copper, in lovely blue and green shades.

Other notable sources include:

  • United States: California; Nevada; Utah (various localities).
  • France: Cap Garonne.
  • Algeria; Chile; Germany; Italy; Turkey.

Stone Sizes

Violet crystals, noted up to 1 cm long and transparent, would yield stones up to about 1-2 carats. Green material, usually not clean, would provide only small faceted gems (1-3 carats).

  • Private Collection: 4.38 (pink, Mexico).

Care

Adamites have a low hardness of 3.5 and good cleavage. Thus, they make less than optimal pieces for jewelry use. You’ll find these stones more likely in gem collections as crystal specimens than in jewelry collections. See our gemstone jewelry cleaning guide for care recommendations.

Manganoan adamite - Mexico
“Manganoan Adamite and Lotharmeyerite,” Ojuela Mine, Mapimí, Mun. de Mapimí, Durango, Mexico, by Didier Descouens. Licensed under CC By-SA 3.0. (Here, lotharmeyerite occurs as tiny, dark red crystals).