The Carlsbad laboratory recently had the chance to examine a 4.60 ct cushion-cut zircon with truly unusual color behavior.

Recently, a 23.67 ct pear cabochon aquamarine with light greenish blue color and poor clarity was sent to the Taiwan Union Lab of Gem Research (TULAB) for identification.

This study examines FTIR spectra of yellow sapphire heat treated in an oxidizing atmosphere to deepen its color.

Fura Gems hosted its first sales event for rough Mozambican rubies in August and September 2021.

A study on heat with pressure treatment of blue sapphires reveals FTIR patterns associated with different iron concentrations.

Careful comparison of two GIA reports reveals a fraudulent inscription on a laboratory-produced diamond presented as a natural.

Figure 1. The vivid colors seen in fine gem-quality spinel are derived from the mixing between multiple different chromophores in a range of ratios and concentrations, as in this fine 13.52 ct violetish purple spinel. Courtesy of the Dr. Edward J. Gübelin Collection. Photo by Robert Weldon/GIA.

Extensive analysis of early beads and pendants from archaeological sites in the French islands of the Lesser Antilles identified the objects as sudoite, which has never before been documented in any lapidary production.

Reports on the geology, background, and current state of mining and production at Iran’s largest turquoise mine.