Article Search Results

Show Filters
Showing 310 results for "*"
Figure 9. The parcel of rough spinel on the left, reportedly from Tajikistan, contains pieces weighing up to 48.5 g. The seven faceted spinels on the right (9.04–28.16 ct) were fashioned from some of this rough.
Purplish Pink Spinel from Tajikistan: Before and After Cutting

Purplish Pink Spinel from Tajikistan: Before and After Cutting

Read More

Suite containing over 36 carats of Yogo sapphire
Gemmological Characterisation of Sapphires from Yogo Gulch, Montana

A look at the mining and distinguishing characteristics of this naturally vibrant blue sapphire.

Read More

Timeline showing the use of garnets in different eras from 300 BCE to 700 CE
An Early Byzantine Engraved Almandine from the Garibpet Deposit, Telangana State, India: Evidence for Garnet Trade Along the Ancient Maritime Silk Road

Analyses the chemical composition and inclusion characteristics of this ancient artefact.

Read More

Gerd Dreher agate lily and Patrick Dreher citrine mouse
Gem Virtuosos: The Drehers and Their Extraordinary Carvings

A look at the artistic heritage of the Drehers, an influential family of gem carvers in Idar-Oberstein, Germany.

Read More

A blue synthetic star sapphire from past production of Wiede’s Carbidwerk
Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany

Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s until the 1970s.

Read More

Fabergé figures of Chamber Cossacks A.A. Kudinov and N.N. Pustynnikov
Fabergé Cossack Figures Created from Russian Gemstones

Hardstone figures of two Russian imperial bodyguards, commissioned in 1912 by Nicholas II, demonstrate the House of Fabergé’s meticulous detail and craftsmanship.

Read More

Beryllium Diffusion of Ruby and Sapphire

The heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800°C has become a major issue in the gem trade.

Read More

G. Robert Crowningshield: A Legendary Gemmologist

G. Robert (Bob) Crowningshield has made many significant contributions to the study of gems and the science of gemmology.

Read More

The 3543 CM-1 Infrared Absorption Band in Natural and Synthetic Amethyst and its Value in Identification

The proper use and limitations of IR spectroscopy for identifying natural versus synthetic amethyst of various types have been investigated, focusing on the region 3800–3000 cm-1.

Read More

A Gemological Pioneer: Dr. Edward J. Gübelin

During a career that spanned more than 65 years, the eminent Swiss gemmologist Dr. Edward J. Gübelin (1913–2005) built a monumental legacy.

Read More