ペリドット、スピネル、サードニックスが8月の3つの誕生石です。ペリドットの誕生石は、苛酷な条件の下で形成されることで知られています。地球のマントルの奥深くから溶岩とともに運び出され、その溶岩が凝固した際に発見されたり、宇宙から旅した ...

Blue sapphires are currently being mined on an exploratory basis from alluvial deposits at the Lindi mine, near the town of Mingxi in Fujian Province. The geology and occurrence of the sapphires ...

This little-known source of gem-quality peridot, located in southwestern New Mexico, produces small but brilliant gems. Kilbourne Hole peridot is found in the explosion debris of a 180,000-year-old ...

An emerald deposit at Byrud, in southern Norway, yielded significant quantities of crystals and gem rough in the late 19th and early 20th centuries. Complex multiphase inclusions in the emeralds ...

11月生まれの方は、2つの美しい誕生石、トパーズとシトリンからお好きなものを選ぶことができます。トパーズには虹のように様々な色があります。そしてシトリンには魅力的な黄色やオレンジの色相があります。これら2つの11月の誕生石は、両方とも心を ...

Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources were studied by laser ablation–inductively coupled plasma–mass spectrometry (LAICP- MS). Among ...

Following up on Nassau's 1981 article on the technical aspects of heat treating ruby and sapphire, the author reports his personal observations of the actual heat treatment process in Bangkok. He ...

The world's first commercially available synthetic cat's-eye alexandrite chrysoberyl is now being manufactured and marketed by the Kyocera Corporation in Kyoto, Japan. Kyocera markets synthetic ...

Figure 1. The largest known natural moissanite crystal, found along the Kishon River in northeastern Israel, measures 4.1 mm in its longest dimension. Photo by Vered Toledo. Synthetic silicon carbide ...

Since Robert Crowningshield's discovery in the late 1950s that diamonds that have been artificially colored by irradiation and subsequent annealing could be identified by their characteristic ...

Synthetic emeralds grown hydrothermally in an alkali-free, chlorine-bearing solution have been manufactured in Guilin, China, since 1987. Diagnostic microscopic features include growth and color ...

Through a unique combination of hands-on training, one-on-one coaching and multimedia, the Diamond Grading class explores how to grade diamonds consistently and accurately using a modern gem ...