G. Robert (Bob) Crowningshield has made many significant contributions to the study of gems and the science of gemmology.
Read MoreDuring a career that spanned more than 65 years, the eminent Swiss gemmologist Dr. Edward J. Gübelin (1913–2005) built a monumental legacy.
Read MoreThe GIA diamond cut grading system described here includes the components of brightness, fire, scintillation, polish and symmetry, as well as weight and durability concerns, into a single overall grade for cut quality for standard round brilliants.
Read MoreThis article describes what is known about the Wittelsbach Blue since it was first reported in 1666, and the gemmological information released to date on this diamond.
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A peridot-like bright greenish yellow to green gem material called “green amber” has recently appeared in the gem market.
Read MoreGems & Gemology, the professional quarterly of GIA, debuted in 1934
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This article explores and identifies the changes that type IIa GE POL diamonds experience before and after HPHT annealing.
Read MoreA treatise on the design, display, care and repair of fine gemstones.
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The filling of surface-reaching breaks in emeralds is a relatively common practice, for which various kinds of oils and a natural resin have historically been used.
Read MoreLow levels of radioactivity were found in some greenish yellow to yellow-green (peridot-like) synthetic spinel-and-glass triplets, mirror-backed glass rhinestone chatons and fully fashioned glass rhinestones.
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