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

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 ...

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 ...

Verifying the gold content of karat-gold jewelry is a problem for the entire industry. This study compares four widely available testing methods: density (measured by hydrostatic weighing), chemical ...