Figure 1. These emeralds from Musakashi, Zambia, range from 0.57 to 4.85 ct. The rough samples were polished with one window on each. The faceted sample measures 6.29 × 5.35 × 3.53 mm and weighs 0.97 ...

Natural pearls grow in the wild without human intervention. They are very rare, and most natural pearls in the market today are antique. Cultured pearls are grown in pearl farms, and are the direct ...

This amethyst crystal is from Namibia. It shows classic quartz crystal shape: a six-sided columnar crystal with a pyramid-shaped termination at the top. Courtesy Daniel Trinchillo, Fine Minerals ...

Figure 1. The color zoning of amethyst from Boudi often displays a characteristic hourglass shape. Photo by Abdelghani El Harfi and Salahaddine Mouaddib. For 25 years, the Moroccan locality of Boudi ...

This 7.19-carat alexandrite was cut to feature its beautiful color change. When the light source changes from daylight to incandescent light, the gem’s color changes from bluish green to reddish ...

Consumers now, more than ever, have a heightened awareness of sustainably and ethically sourced products. The GIA Diamond Origin Report uses scientific evaluation to provide confirmation of a ...

A new diamond imitation, synthetic moissanite (silicon carbide), is now being produced by C3 Inc. in near-colorless form for jewelry purposes. With refractive indices of 2.648 and 2.691, a dispersion ...

By contrast, the pearls sometimes labeled as “Chinese akoyas”, “baby akoyas”, or “freshwater akoyas (AK)” are freshwater ...

Figure 1. This demantoid was faceted to better reveal the “horsetail” inclusions. The sample is 8 mm in diameter. Photo by U. Hennebois. The exact origin and composition of the “horsetail” inclusions ...

Figure 1. Top left: Rubies are mined in a mango orchard in Channapatna, India. Top right: This 15 kg rough ruby is from Subramaniam, in the Indian state of Karnataka. Photos by Pooja Shirole. Bottom ...

An 11.23 ct purplish pink cabochon exhibiting multiple cat’s-eye phenomena was recently submitted to the Tokyo laboratory for identification (see above, left). Standard gemological testing results ...

With the withdrawal of Soviet troops from Afghanistan, villagers in the Panjshir Valley are turning their attention to the emerald riches of the nearby Hindu Kush Mountains. Large, dark green crystals ...