Quality assurance testing in the Bangkok lab reveals HPHT synthetic melee in larger sizes.

Optical activity is studied using a polished block of ametrine.

Chatoyancy, rarely seen in play-of-color opal, is observed in Ethiopian material.

Imitation pearls show kaleidoscopic colors with illumination.

Sapphires from Baw Mar host multiphase inclusions in appealing patterns.

Recounts the history, geology, and notable localities of diamond mining in Brazil, and outlines plans for future diamond production.

Investigates the properties of synthetic zincite produced by industrial kilns in Poland.

Identifies 13 copper-bearing tourmalines, which have traditionally been assumed to be elbaite species, as liddicoatite.

A report on a new Ethiopian source of high-quality emerald.

Activity at Brazil’s Belmont mine is updated at Tucson.

A new mining operation in Montepuez is profiled.

Plastic Amber Imitation in a Rosary | Gems & Gemology

An eye-catching replica from a cult TV favorite is found in Tucson.

An update on Nigerian colored stone production is obtained at the Tucson gem shows.

An overview of the trends reported at the 2017 Tucson gem shows.

Describes the occurrence of iridescence, and the role of differential etching, in quartz crystals from India’s Jalgaon District.

A topaz hosting a group of inclusions is examined in the Carlsbad lab.

A rare find from a limited occurrence in Tanzania’s Merelani Hills, along with a “Merelani mint” garnet, is seen in Tucson.

《宝石与宝石学》 2017 年春季刊摘要。

Three mineral species, not previously seen in the Carlsbad lab, are examined.