Proposes a formation model for sapphire from the main deposits in southern Vietnam based on the chemical composition of their mineral inclusions.

A creative imitation using fused bluish green glass with copper platelets poses as Paraíba tourmaline.

本研究では、バンコクのラボラトリーが、現地の真珠養殖場から直接採取された5つの低品質の有核養殖真珠を検査し、加工の前後の特徴を記録しました。

Geographic origin determination relies on a combination of gemological observations and advanced analytical tools. This contribution reviews the analytical methods commonly used to establish origin.

Examines a very large dataset of colorless to near-colorless diamonds submitted to GIA and evaluates their diamond type and spectroscopic properties.

Magnetite inclusions in a four-rayed star peridot help to date its terrestrial age.

GIA Johannesburg identifies fraudulent GIA inscriptions on several synthetic moissanites submitted as diamonds.

Presents spectroscopic and chemical analysis of a new variety of turquoise with a rare raindrop pattern with saturated colors.

“Star cruisers” formed of ferrocolumbite seem to fly in a large topaz crystal from the Shigar Valley in Pakistan.

A 60.71 ct cabochon was recently submitted to the Tokyo lab for identification.

The Carlsbad laboratory received for examination two dark-colored bead cultured pearls embedded with an electronic device from Jeremy Shepherd, CEO of Pearl Paradise.

Reports on a visit to a shell nucleus manufacturer and two pearl farms in northern Vietnam, which is emerging as a notable producer.

Presents a detailed study of gemological properties, inclusion features, spectroscopic characteristics, and chemical composition of emeralds from this important source.

Chronicles important auctions of jewels from European royal collections over the years, with a focus on a recent high-profile sale of items that once belonged to Marie Antoinette.

ニューヨークのGIAラボラトリーは先日、素晴らしい真珠を検査する機会を得て、さらに素敵な話も聞くことができました。

A rough diamond crystal weighing 4.05 ct was observed with radiation staining on its surface.

Gem silica, also known as “chrysocolla chalcedony,” is considered the most valuable variety of chalcedony.

Presents the four major groups of defects responsible for the color in nearly all yellow and orange diamonds.

Examines the effectiveness of hydrogen and oxygen isotopes in discriminating dolomite-related nephrites from the four most important occurrences worldwide.

Scientists in Russia construct an origin story through the analysis of petrified wood popularly used in the souvenir trade.