Four atypical bead cultured pearls with variations on two types of nuclei are examined in the Mumbai laboratory.

Evaluates the growth mechanisms of special morphological features in Colombian emerald, including possible relationships to trapiche emeralds and samples displaying the gota de aceite effect.

Microscopic examination of a ruby at the Carlsbad laboratory reveals synthetic overgrowth indicative of high-temperature heat treatment.

A look at the largest CVD diamond GIA has encountered to date.

GIA researchers report on a new nickel-diffusion treatment used to modify color in spinel and present criteria for identification.

Examines the use of strong fluorescence near 394 nm under 320 nm excitation as a potential means of identifying copper diffusion treatment of feldspar.

The Carlsbad laboratory reports on a Fancy Deep brownish yellowish orange diamond featuring trigons within subsurface etch channels.

A rare inclusion is reported in ruby from the Mogok mine for the first time.

The Tokyo laboratory examines a 126 ct cat’s-eye emerald from Brazil.

Fiber-optic illumination reveals an electromagnetic wave-like pattern of particles in a ruby from Myanmar.

Characterizes turquoise treated with an inorganic additive that dramatically improves the luster and color of low- and medium-quality material.

Examination of a yellowish green demantoid reveals fibers of serpentine in a randomly curved pattern and a columnar two-phase negative crystal.

Profiles a groundbreaking gem artist on a quest to bring new concepts, techniques, and products to the industry.

Documents heating experiments conducted on Burmese rubies to find useful indicators of heat treatment at temperatures below 1200°C.

This installment of “Colored Stones Unearthed” covers gemstones that formed in magmatic environments and the insights they offer into the evolution of the earth and the geological processes that shaped our world.

A very large baroque white pearl is further examined in the Mumbai laboratory due to its suspicious heft.

A successful spring season set high expectations for colored diamonds at auction in late 2022.

A bluish green omphacite crystal is discovered in a Fancy brown-pink diamond.

An overview of the Winter 2022 Gems & Gemology content.

A comprehensive look at the gemological features and advanced analysis of blue and fancy-color sapphire from the agricultural area of Muling, China.