Figure 1. Left: 18K yellow gold “Flames” ring with 25.19 ct Mexican fire opal. Right: This 18K yellow gold “Spice” ring ...

The authors examine the gemological properties and commercial potential of a new source of amber, discovered in 2020 on the Vietnamese island of Phu Quoc. It is the only known amber locality in ...

Aquamarine and heliodor are colored by Fe ions, an important coloring agent for beryl. Blue to yellow gem beryl was studied by quantitative spectroscopy and trace-element analytical techniques to ...

Examination of a 0.50 ct H-color type Ia natural diamond with SI 2 clarity recently revealed intriguing inclusions. Under the microscope, one crystal inclusion seen with a mirror reflection resembled ...

Recently, the author examined a faceted blue oval sapphire. Standard gemological properties and chemical analysis indicated a geographic origin of Kashmir. Microscopic examination revealed internal ...

Chemical vapor deposition (CVD) technology has been widely used to grow diamonds for the jewelry market, targeting popular colors and sizes. The majority of these products are colorless to ...

GIA’s Bangkok laboratory received for identification a set of 35 loose non-nacreous pearls displaying a wide range of bodycolors including white, orange, pink, brown, purple, and black. The pearls ...

The published literature offers only a few records of direct measurement of the natural radioactivity in nephrite. The present study used high-purity germanium (HPGe) low-background gamma-ray ...

Recently, the authors examined a 0.36 ct diamond with D color and SI 2 clarity. The diamond contained a cluster of cloud inclusions arranged to form an interesting pattern (see above). Best observed ...

A 1.09 ct D-color diamond grown by chemical vapor deposition (CVD) was recently submitted to the Mumbai laboratory. This submission displayed an interesting blue band, seen through the pavilion facets ...

The authors recently examined two oval double cabochons consisting of chalcedony quartz, each with a multitude of glistening metallic native copper inclusions (figure 1, left). These gems were ...

Recently the author examined a 0.95 ct diamond with a special note. It only took one and a half beats to discover a dark crystal with a straight stress cleavage crack shaped like a dotted quarter note ...