This synthetic ruby specimen features two growth methods within the same crystal.

Examination of two CVD synthetic diamonds with an unusual Fancy Dark gray color.

Overview and commentary on the 2013 The Journal of Gemmology article “Peñas Blancas: An Historic Colombian Emerald Mine."

Overview and commentary on the 2014 Journal of Gemmology article “Purple to Reddish Purple Chrysoberyl from Brazil.”

Examines the internal structure, chemical composition, and spectroscopic features of 22 pen pearls.

Describes the phenomenon of pleochroism and its complex effect on the appearance of colored stones.

Introduces the Chinese nephrite mine in Hechi and characterizes the “band” and dendritic patterns found in this material.

This aquamarine's most striking feature was its unusually strong dichroism, displaying very deep blue and pale bluish green colors.

The Indian Gemological Institute’s Gem Testing Laboratory recently examined a 0.30 ct colorless round brilliant-cut diamond containing an interesting inclusion.

This giant clam pearl was noteworthy for its size and interesting coloration, and its pronounced banding when viewed with transmitted light.

Review of Stefano Papi’s Jewels of the Romanovs: Family & Court.

Review of Ronald McIntosh and Warren Anderson's Kentucky Agate: State Rock and Mineral Treasure of the Commonwealth.

Review of Richard Hughes’s Ruby & Sapphire: A Collector’s Guide.

Review of Suzanne Ramljak's Unique by Design: Contemporary Jewelry in the Donna Schneier Collection.

A summary of gemological presentations from the 21st IMA General Meeting in Johannesburg.

Review of Paul Koudounaris’s Heavenly Bodies: Cult Treasures and Spectacular Saints from the Catacombs.

An investigation of a coated fire opal recently found in the Chinese market.

Review of Martin Chapman and Amanda Triossi’s The Art of Bulgari: La Dolce Vita and Beyond, 1950–1990.

Reports on the first discovery of fine topazolite garnet crystals in Mexico.

カリフォルニア州産の宝石