Abstracts of speaker presentations from the “Gem Characterization” session of GIA’s 2018 International Gemological Symposium.

Poster abstracts on “Gem Characterization” from GIA’s 2018 International Gemological Symposium.

秋季，大自然赐予我们色彩亮丽的变色树叶，还有缤纷落日照射形成的绚丽万花筒。

The DiamondView instrument is able to identify glass as the filler in a pair of heart-shaped rubies.

The first known group of color-change gem-quality chrome grossular garnet, reportedly from Ethiopia, is examined in GIA’s Carlsbad lab.

Gold: Vortex, Virtues, and Values was hosted by Initiatives in Art and Culture (IAC) at Bohemian National Hall in New York City, April 12–13. Now in its eighth year, the conference has become an annual industry gathering for those looking to evaluate the market, discover exceptional work, and discuss key gold-related issues.

Projects developed by the GemHub to benefit miners, cutters, and others involved in the gem and jewelry industry.

An update the gemological and chemical characteristics of golden sheen sapphires from Kenya.

aser confocal microscopy, a very reliable method of revealing surface micro-features, is used on an HPHT synthetic diamond to reveal growth structures.

A transparent greenish blue pear-shaped gemstone, reportedly from Madagascar, is discovered to be a Maxixe-type beryl.

A jade bracelet contains unusual fillers, used to create a smooth surface.

An unusual assembled stone is examined at GIA’s New York lab.

Rare pearls, along with their shell, are studied in the Hong Kong lab.

A synthetic diamond seen in the Carlsbad lab is the largest faceted lab-grown diamond examined by GIA.

Irradiated CVD-grown diamonds are examined in the Carlsbad lab.

A sapphire cabochon with an unusual appearance is seen at GIA’s Tokyo lab.

Over the last decade, the production methods used to create synthetic diamond melee have improved substantially, along with the quality of the specimens themselves.

Crassostrea virginica, the so-called Eastern or American oyster, is a commercial seafood widely distributed along the east coast of the United States to the Gulf of Mexico.

Lotus Gemology receives submissions of star stones on a regular basis, so when we first saw the specimen shown here, it appeared to be one among many of our usual stones to test.

Aesthetically pleasing inclusions are found in topaz from Pakistan’s Shigar Valley.