Augelite Value, Price, and Jewelry Information


triangle-cut augelite - California
Colorless, triangle-cut augelite, 0.41-ct, 6.3 x 5.3 mm, Champion Mine, Mono Co., California. © The Gem Trader. Used with permission.

Soft and brittle, rare augelites are difficult to cut and unsuitable for wear. Faceted transparent pieces are only found in very complete gem and mineral collections.

Augelite Value

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

Augelite Information

DataValue
NameAugelite
Crystallography  Monoclinic. Crystals tabular and thick; prismatic; acicular. Also massive.
Refractive Index 1.570-1.590
Colors Colorless, white, yellowish, pale blue, pale rose, pink, green.
Luster Vitreous. Pearly on cleavage surfaces.
Fracture Uneven
Hardness 4.5-5
Specific Gravity 2.696-2.75
Birefringence 0.014-0.020
Cleavage Perfect 1 direction, good 1 direction
Dispersion None.
Luminescence Usually none, but green Peruvian material has shown light yellow fluorescence in SW, inert in LW.
Transparency Transparent.
Absorption Spectrum Not diagnostic.
FormulaAl2PO4(OH)3
Pleochroism None.
Optics α = 1.574; β = 1.576; γ = 1.588. White Mountain, California, material: α = 1.570; β = 1.574; γ = 1.590. Biaxial (+), 2V ~ 50°.
EtymologyFrom the Greek word auge for “luster,” due to the mineral’s glassy appearance.
OccurrenceGranitic pegmatites and hydrothermal veins.
Augelite, faceted and rough - California
Augelite: California (~ 1.5, rough ½ inch across). Photo © Joel E. Arem, PhD, FGA. Used with permission.

Comments

Although new gem-quality finds of this phosphate mineral have appeared, augelites remain quite rare. Furthermore, facetable crystals are typically very small and very rarely transparent. With a hardness of 4.5-5, a brittle tenacity, and two planes of perfect and good cleavage, this gem poses some challenges to gem cutters and jewelry enthusiasts alike. Although it can occur in lovely pale greens, yellows, blues, and pinks, as well as colorless, and has a striking vitreous, glass-like luster, augelite has no dispersion or “fire” to catch the eye.

This rough and cut set features a colorless, sharp augelite crystal on quartz and a colorless, round brilliant-cut augelite. 2.1 x 1.3 x 0.8 cm (crystal), 0.95-ct (gem), Champion Mine, Mono County, California, USA. © Rob Lavinsky, www.iRocks.com. Used with permission.

Identifying Characteristics

Gem-quality light green augelites from a new find in Peru in 2006 have shown light yellow fluorescence under shortwave ultraviolet light. Gems from other sources have shown no fluorescence.

step-cut augelite - Peru
Yellowish green, rhomboid step-cut augelite, 1.04 cts, 7.2 x 4.3 mm, Ortega Mine, Ancash Dept., Peru. © The Gem Trader. Used with permission.

Synthetics

Scientists have used synthetic augelites for research purposes. However, there is no known jewelry use for this lab-created material.

Enhancements

No known gem treatments or enhancements.

Sources

Long the only source for facetable augelites, crystals from the Champion Mine in Mono County, California could reach about one inch in size. This source is now depleted. New facetable material has come from Peru.

Yukon Territory, Canada and Bolivia produce fine-quality crystal specimens.

Other notable sources include the following:

  • United States: Palermo Mine, New Hampshire; Keystone, South Dakota (massive, non-gem).
  • Australia; Sweden; Uganda (massive).
augelite crystals - Bolivia
Lustrous augelites in a vug. The largest crystal is 1.3 cm in length. Machacamarca Mine, Machacamarca, Machacamarca District (Colavi District), Cornelio Saavedra Province, Potosi Department, Bolivia. © Rob Lavinsky, www.iRocks.com. Used with permission.

Stone Sizes

Most existing faceted gems from the California material weigh less than one carat. Some weigh up to three carats. This rare mineral very rarely yields larger stones.

Care

Clean augelites only with a soft brush, mild detergent, and warm water. Consult our gemstone jewelry cleaning guide for more recommendations.