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Sapphire
The name “sapphire” can also apply to any corundum that’s not ruby red, another corundum variety.
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Dark Red Tantalite Crystal in Greenish Blue Sapphire
The blunt termination of a red manganotantalite inclusion displays a striking contrast against a greenish blue sapphire.
The Primary Sapphire Occurrence at French Bar Sill Along the Missouri River, Near Helena, Montana
Reports on a new source of primary gem-quality sapphire from Montana, comparing its inclusions and trace element chemistry with those from secondary sources in the state.
Low-Temperature Heat Treatment of Corundum and the Behavior of the 3161 cm–1 Infrared Band
A study analyzing the thermal behavior of the 3161 cm–1 IR feature in 10 natural corundum samples from various deposits.
Quench-Crackled and Dyed Laboratory-Grown Sapphire
The Carlsbad lab receives a laboratory-grown colorless sapphire with weblike fractures containing concentrations of dye.
“Sugar Plum” in Titanium-Diffused Blue Sapphire
A sugar plum–like frosted zircon cluster is observed in a blue sapphire.
Gems Keep Giving
The nonprofit organization Gems Keep Giving aims to improve global small-scale mining and gem-cutting communities.
Update on Montana’s Rock Creek Sapphire
Potentate Mining expands its mining operation and hosts the first Montana sapphire tender in Bangkok.
Irreversible Photochromism in Synthetic Sapphire
The first documented case of corundum with irreversible photochromism encountered at GIA.
The 3309 cm^–1^ Series in Sapphire and Ruby: A Focus on FTIR Peak Position Variation
Investigates the correlations between peak positions in the 3309 cm–1 series with trace element concentrations for ruby, metamorphic and basalt-related blue sapphire, and laboratory-grown sapphire.
Rare Musgravite Crystal in Green Sapphire
A surface-reaching crystal in a green sapphire is identified as musgravite.
New Production of Sapphire from Matepwende, Tanzania
Reports on the study of sapphire samples from a newly discovered source in southern Tanzania.
Unique Fingerprint in Montana Sapphire
A group of fingerprint and crystal inclusions form the shape of a bird in a Montana sapphire.
