Possible Natural Abalone Shell Blister
An intriguing item was sent by KC Bell to GIA’s Carlsbad laboratory for examination.
Cobalt-Coated Sapphire
The New York lab recently identified a sapphire entirely covered with a cobalt coating to enhance its blue color.
Faceted Diamond Octahedron with a Remarkable Stellate Cloud Inclusion
A remarkable inclusion scene in diamond is showcased by an unconventional cutting style.
Laboratory-Grown Sapphire with Unusual Features
The Hong Kong laboratory recently examined a 14.36 ct pink-orange cushion mixed-cut specimen.
Large Laboratory-Grown Star Ruby and Sapphire
The Tokyo lab received two unusually large laboratory-grown star corundum for examination.
Resin Imitation Ivory with a Pseudo “Engine-Turned” Structure
Resin materials marketed as imitation ivory were recently acquired by a GIA gemologist.
Iolite-Sunstone Intergrowth and Inclusions
At the GIA Carlsbad laboratory, the authors recently examined a cabochon of “bloodshot” iolite (containing red, eye-visible platelets of hematite) intergrown with a sunstone.
Quarterly Crystal: “Ball Bearing” in Quartz
Quartz crystals with three-phase fluid inclusions from the Jinkouhe mine in the Sichuan Province of China have been sold for many years at gem and mineral shows such as those held annually in Tucson, Arizona.
New Find of Deep Blue Aquamarine from Nasarawa State in Nigeria
Nigerian aquamarine with exceptionally deep and saturated color also displays unusually strong pleochroism.
A Near-Round Natural Pearl Discovered in the Edible Oyster Magallana bilineata
An edible oyster from the Hab River Delta of Pakistan reveals a natural pearl.
Black Non-Nacreous Pearl Imitations Made of Beads Cut from Shell
The DANAT laboratory recently encountered two natural black color beads cut from an unknown mollusk.
Gemstone Portrait Artist Angie Crabtree
The 2019 AGTA show in Tucson featured the work of a gemstone portrait artist.
Trapiche Emerald from Swat Valley, Pakistan
Minute platy magnetite inclusions in these emeralds from Pakistan could help advance our understanding of trapiche.
The Rare Sun Diamond
An eye-visible cloud with a star-like pattern is highlighted by the cut of the Rare Sun diamond.
Blue Gahnite from Nigeria
LA-ICP-MS analysis helps researchers better understand the composition of this type of spinel from Nigeria.
Dendritic Inclusions of Thorianite in Heated Blue Sapphire
Recently, a 2.05 ct blue sapphire was sent to Guild Gem Laboratories for identification.
Artificial Glass Imitating Blue Amber
Artificial glass, a low-cost material, is capable of simulating any gemstone owing to its range of appearances (bodycolor, transparency, and phenomena).
Opals Revisited
Long-forgotten opals found after 27 years in storage still looked stable and ready to be worked.
Natural-Color Fancy White and Fancy Black Diamonds: Where Color and Clarity Converge
A systematic study of the properties of approximately 500 Fancy white and 1,200 Fancy black diamonds.
Characteristics of Hydrothermally Treated Beeswax Amber
Reveals the process for hydrothermal enhancement of amber and the means of detection.
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