oval-cut milarite - Brazil
oval-cut milarite - Brazil

Milarite Value, Price, and Jewelry Information


Very rare milarite crystals can occur in green and yellow colors. Transparent material can yield small but pleasant looking faceted gems for collectors.

1 Minute Read

Very rare milarite crystals can occur in green and yellow colors. Transparent material can yield small but pleasant looking faceted gems for collectors.

oval-cut milarite - Brazil
Brilliant oval-cut milarite, 2.07 cts, 9.2 x 7.3 mm, Brazil. © The Gem Trader. Used with permission.
Parallel-growth crystals, milarites - Namibia
Cluster of parallel-growth milarites, 1.7 x 1.5 x 1.2 cm, Milarite locality, Rossing Mountains Area, Erongo Region, Namibia. © Rob Lavinsky, www.iRocks.com. Used with permission.

Comments

Milarite belongs to the mineral group named after it. Sometimes called the osumilite group, this group also includes sugilite and other rarely faceted minerals, such as poudretteite and sogdianite.

Identifying Characteristics

Milarite was originally known as a green mineral, until fine yellow crystals were discovered in Mexico in 1968.

Some milarites may luminesce. Shortwave (SW) ultraviolet (UV) light may cause bluish white or greenish white fluorescence and phosphorescence, while longwave (LW) UV light may cause medium chalky green fluorescence and weak phosphorescence.

milarites - Mexico
Yellow-green milarites on white valencianite, milarite crystals up to 0.6 cm across, Valenciana Mine, Guanajuato, Mun. de Guanajuato, Guanajuato, Mexico. © Rob Lavinsky, www.iRocks.com. Used with permission.

Enhancements

No known gemstone treatments or enhancements.

Sources

Guanajuato, Mexico produces yellow and yellow-green gem-quality crystals on matrix, and some larger Mexican crystals have transparent areas suitable for cutting.

Minas Gerais, Brazil and Tsumeb and the Erongo region in Namibia have also yielded small, facetable material.

Faceted gem - Namibia copy - FI
Milarite: Tsumeb, Namibia (0.53 cts). Photo © Joel E. Arem, PhD, FGA. Used with permission.

Other notable crystal sources include the following locations:

  • St. Gotthard, Switzerland: green crystals.
  • China; Spain; New Hampshire, United States.
crystal - Spain
Milarite crystal, Venero 1 Quarry, Cadalso de los Vidrios, Madrid, Spain. Photo by Christian Rewitzer. Licensed under CC By-SA 3.0.

Stone Sizes

Crystals can occur up to about 4 cm across, but facetable areas in such crystals are very small. Thus, stones over 1 carat could be considered large for the species.

freeform-cut gem
Freeform-cut milarite, 0.98 cts, 8.9 x 6.1 mm, Minas Gerais, Brazil. © The Gem Trader. Used with permission.

Care

With a hardness of 5.5 to 6 and no cleavage, milarites could make suitable jewelry stones if worn with protective settings. However, you're more likely to find them — if at all — in mineral collections than jewelry collections.

Stay on the safe side and refrain from cleaning these rare gems in mechanical systems. Instead, use a soft brush, mild detergent, and warm water. Consult our gemstone jewelry care guide for more recommendations.

  • milarite rough and cut set - Brazil
  • milarite crystal - Brazil
  • emerald-cut milarite - Brazil

    Milarite rough and cut set (crystal: 1.4 x 1.3 x 1.3 cm; emerald-cut gem: 1.38 cts), Jaguaracu, Minas Gerais, Brazil. © Rob Lavinsky, www.iRocks.com. Used with permission.


    Joel E. Arem, Ph.D., FGA

    Dr. Joel E. Arem has more than 60 years of experience in the world of gems and minerals. After obtaining his Ph.D. in Mineralogy from Harvard University, he has published numerous books that are still among the most widely used references and guidebooks on crystals, gems and minerals in the world.

    Co-founder and President of numerous organizations, Dr. Arem has enjoyed a lifelong career in mineralogy and gemology. He has been a Smithsonian scientist and Curator, a consultant to many well-known companies and institutions, and a prolific author and speaker. Although his main activities have been as a gem cutter and dealer, his focus has always been education. joelarem.com


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