Nambulite Value, Price, and Jewelry Information

Optics:a = 1.707; β=1.710; γ=1.730.

Biaxial (+), 2V= 30°.

Occurrence: Nambulite is a rare mineral reported in crystals up to 8 mm long at the Tunakozawa Mine, Northeast Japan. These crystals are found in veins cutting manganese oxide ores. Much larger crystals, up to approximately 3 cm across, have more recently been found in Namibia, at the Kombat Mine, near Tsumeb. I have seen a completely transparent crystal in a private collection that would yield about 20-25 carats of flawless faceted gems, the largest of these perhaps 10 carats in weight.

Comments: The color of Namibian nambulite is a striking orange-red, very intense, and not really like any other gem I have seen. Cut stones would be both extremely rare and quite magnificent, perhaps bearing some similarities to rhodonite.

Name: After Professor Matsuo Nambu of Tohoku University, Japan, for his studies of manganese minerals.

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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