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      Anglesite Value, Price, and Jewelry Information

      This Portuguese-cut, rich, lemon-yellow anglesite was custom cut by Spectrum Award winner Mark Kaufman. 62.27 cts, 24.0 x 17.0 x 11.0 mm, Touissit, Oujda-Angad Province, Oriental Region, Morocco. ? Rob Lavinsky, www.iRocks.com. Used with permission.

      Anglesite

      Although anglesites with pale colors can show great dispersion and brightness, they’re difficult to cut and inadvisable to wear. Faceted pieces are true rarities, seldom seen except in very complete gem collections.

      Anglesite Value

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

      Anglesite Value via Gem Price Guide

      Accompanying value information:
      Faceted 10 carat plus
      to /ct

      Anglesite Information

      Data Value
      Name Anglesite
      Colors Colorless, white, yellowish gray, lemon to golden yellow, brownish orange, pale green, and blueish shades.
      Crystallography Orthorhombic. Crystals usually tabular, prismatic; granular; massive; stalactitic.
      Refractive Index 1.877-1.894
      Luster Adamantine to vitreous.
      Hardness 2.5-3
      Wearability Poor
      Fracture Conchoidal
      Specific Gravity 6.30-6.39; usually 6.38.
      Birefringence 0.017
      Cleavage Good 1 direction
      Dispersion 0.044
      Heat Sensitivity Yes.
      Luminescence Weak yellowish fluorescence in SW and LW.
      Luminescence Present Yes
      Luminescence Type Fluorescent, UV-Long, UV-Short
      Enhancements Bleaching.
      Transparency Transparent to opaque.
      Absorption Spectrum Not diagnostic.
      Formula

      PbSO4

      Pleochroism

      None.

      Optics

      α = 1.877; β = 1.883; γ = 1.894.?Biaxial (+), 2V ~ 75°.

      Optic Sign Biaxial +
      Etymology

      Named after the type locality, the Isle of Anglesey, Wales, UK.

      Occurrence

      Secondary mineral in lead deposits, formed by oxidation of galena (PbS).

      Faceted Anglesite - Tsumeb, Namibia

      Anglesite: Tsumeb, Namibia (16.1, 16.2). Photo ? Joel E. Arem, PhD, FGA. Used with permission.

      Comments

      Anglesite’s fire or dispersion equals that of diamond (0.044). If properly faceted, this gem can also show magnificent brilliance. However, due to its hardness of 2.5 to 3 and good cleavage, cutting requires great care.

      Where anglesite occurs massively, it serves as a lead ore.

      Identifying Characteristics

      Anglesite’s specific gravity (SG) of 6.30 to 6.39 places it among the densest gem materials. Testing for SG can usually distinguish it from gems of similar appearance. However, two other rarely faceted collector’s gemstones have a comparable range of colors, hardness, and SG. Like anglesite, cerussite and phosgenite can be colorless as well as white, grayish, yellowish, or greenish. Their fluorescence under ultraviolet light (UV) can also appear yellowish.

      Comparison of Selected Physical and Optical Properties of Anglesite, Cerussite, and Phosgenite

      Hardness SG Fluorescence in UV Refractive Index Optic Character
      Anglesite 2.5-3 6.30-6.39 Weak yellowish. a = 1.877; b = 1.883; γ = 1.894 Biaxial (+)
      Cerussite 3-3.5 6.55 Can be yellow in LW. Pale blue/green in SW. a = 1.804; b = 2.076; γ = 2.079 Biaxial (-)
      Phosgenite 2-3 6.13 Strong yellowish. o = 2.114-2.118; e = 2.140-2.145 Uniaxial (+)

      A refractive index and an?optic character reading with a refractometer?and/or?polariscope may be the most effective way to distinguish these gems. However, keep in mind that phosgenite may be anomalously biaxial. Some greenish phosgenites may show weak pleochroism, while anglesite has none.

      Cut Anglesite - Brazil

      “Cut Anglesites,” Minas Gerais, Brazil. Gem cutting by Afonso Marques. Photo by Eurico Zimbres. Licensed under CC By-SA 3.0.

      Synthetics

      Laboratories have synthesized anglesite crystals for geological research. However, there is no known use of this material for jewelry purposes.

      Enhancements

      In the early 1980s, amber-red anglesites from Touissit, Morocco were found to be the result of bleaching colorless and pale yellow crystal specimens. This treatment produced surface-deep colors. Only immersion in a bromide-water solution could reverse this coloration.

      canary yellow anglesite crystal - Morocco

      Rob Lavinsky first suspected this canary yellow to colorless anglesite from the late 1970s/early 1980s finds at Touissit to be a bleached specimen. (This treatment also produced orangey yellow colors). However, the colors of this crystal go through to the core, unlike those of surface treated material. These colors are, indeed, natural. 2.1 x 1.3 x 0.4 cm, Touissit, Oujda-Angad Province, Oriental Region, Morocco. ? Rob Lavinsky, www.iRocks.com. Used with permission.

      Sources

      Although many localities across the globe can potentially yield gemmy crystals, only a few produce colorless and pale brown specimens.

      Touissit, Morocco produces gem crystals in immense sizes for this species.

      Tsumeb, Namibia produces large transparent yellowish crystals and, sometimes, gemmy colorless specimens.

      Other notable gem-quality sources include:

      • United States: Arizona; Coeur d’Alene district, Idaho; New Mexico; Chester County, Pennsylvania; Tintic, Utah.
      • Broken Hill, N.S.W., Australia; Brazil; Germany; Chihuahua, Mexico; Russia; Sardinia; Slovenia; Dundas, Tasmania; Tunisia; England, Scotland, Wales, United Kingdom.
      anglesite - Mexico

      “Anglesite,” 4.1 x 3.6 x 2.8 cm, Erupcion Mine, Villa Ahumada, Chihuahua, Mexico. ? Rob Lavinsky, www.iRocks.com. Used with permission.

      Stone Sizes

      Faceted anglesites typically range from 1 to 6 carats. Very rarely does this material occur large enough to cut anything bigger than this. However, some rough, notably from Namibia and Morocco, has yielded 100+ carat gems. One such stone from Tsumeb, at 300 carats, broke during cutting!

      • Devonian Group (Calgary, Alberta, Canada): 88.75 (yellow, coffin-shaped triangle, Tsumeb, Namibia).
      • Royal Ontario Museum (Toronto, Ontario, Canada): 23.62 (colorless, step cut, Tsumeb).
      • National Museums of Canada (Ottawa, Ontario): 25.90 (yellow, scissors cut, Morocco).
      • Private Collections: 126 (light golden brown, Morocco); 73 (yellow-orange, cushion cut, Morocco); 63 (lemon yellow emerald cut, Morocco); 171.12 (medium orange, Morocco); 169 (oval, Morocco).

      Care

      Anglesites contain lead. When cutting this material, avoid ingesting or inhaling particles and wash your hands.

      Jewelry use is not recommended.

      Faceted Anglesite - Morocco

      Anglesite: Morocco (6.99). Photo ? Joel E. Arem, PhD, FGA. Used with permission.

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