faceted yugawaralite
faceted yugawaralite

Yugawaralite Value, Price, and Jewelry Information


Yugawaralite is a very rare colorless to pinkish zeolite mineral. Little facetable material exists, so a cut yugawaralite would be a prized addition to a gem collection.

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Yugawaralite is a very rare colorless to pinkish zeolite mineral. Little facetable material exists, so a cut yugawaralite would be a prized addition to a gem collection.

faceted yugawaralite
Yugawaralite, 1.01 cts. Photo © Joel E. Arem, PhD, FGA. Used with permission.
yugawaralite crystals - Mumbai, India
Yugawaralite from Mumbai, India, from the collection of the A. E. Seaman Mineral Museum, Houston, Michigan. Photo by Chris857. Licensed under CC By-SA 3.0.

Comments

The Kandivali Quarry near Mumbai, India has produced superb, well-formed colorless and transparent crystals close to the literature values for yugawaralite. A few faceted gems have been cut from this exceptional and extremely rare material.

Identifying Characteristics

Yugawaralites have both pyroelectric and piezoelectric properties. This means they generate electricity when heated and placed under pressure, respectively.

tabular yugawaralite crystals - India
Transparent, tabular yugawaralite crystals, the longest measure 0.7 mm. Malad Quarry (Kandivali Quarry), Malad, Ward 38, Mumbai (Bombay), Mumbai District (Bombay District), Maharashtra, India. Photo by Gianfranco Ciccolini. Public Domain.

Synthetics

Scientists have synthesized yugawaralites as well as other zeolites for chemical and mineralogical research. However, there is no known jewelry use for this synthetic material.

Enhancements

None known.

Sources

Japan, notably Honshu Island, produces gemmy material. Yugawara Hot Spring, Kanagawa Prefecture is the type locality for yugawaralite.

India, most notably the Kandivali Quarry, produces small amounts of facetable material.

Other notable crystal sources include the following:

  • United States: Alaska; Washington; Yellowstone National Park, Wyoming.
  • British Columbia, Canada; Iceland; Sardinia, Italy; Réunion Island.
yugawaralite - Reunion Island
Yugawaralite (picture width: 20 x 10 mm), Cirque de Cilaos, Piton des Neiges, Réunion Island. Photo by Michel Poullaouec. Public Domain.

Stone Sizes

The Kandivali Quarry can produce gem-quality crystals up to 3 cm long.

Care

You're more likely to find yugawaralites, if at all, in gem collections than jewelry collections. If used in jewelry, these stones would require protective settings and occasional wear only. Their hardness of 4.5 means they can be scratched very easily, and their very brittle tenacity means they're more likely than most gems to fracture from impact. Clean these gemstones only with a warm damp cloth, mild detergent, and soft brush. For more care recommendations, consult our gemstone jewelry cleaning guide.

yugawaralite - Japan
Yugawaralite from Toi-cho, Shizuoka Province, Japan, on display at the Natural History Museum, Berlin. Photo by Alice Chodura. Licensed under CC By-SA 3.0.

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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