Detection of heat treatment below 1200°C in ruby and sapphire can present challenges to gemologists. In this study, the authors heated Burmese ruby samples and detailed the features that help in the detection of heat treatment.

At the Lotus Gemology laboratory in Bangkok, we often get parcels of relatively uniform stones. But sometimes it is in this routine testing that we uncover surprises.

An apatite crystal appears to float, suspended over a rutile silk cloud in a star sapphire.

The early history of beryllium diffusion in sapphire, starting with the 2001 appearance of large numbers of padparadscha sapphires in the Thai gem market.

The history of the Black Prince's Ruby, one of the world's most famous precious stones.

A brief history of Burmese (Myanmar) sapphires, along with details of some of the major pieces of yore.

An essay on buying gems at the source in Asia, with a discussion of how con men play on the greed of those who believe gems will be cheaper at the mines.

The history of glass-infilling in blue sapphire, along with a description of the latest treatment generation developed in Chanthaburi, Thailand.

Developing a comprehensive colored stone grading system has been the dream of gemologists since the late 1970's, but despite a number of valient attempts, we are no closer to the goal today than we were four decades ago. This article examines the various problems of colored stone grading, explaining why the challenges are at least an order of magnitude greater than the grading of diamonds.

Corundum

Richard W. Hughes  |  1990

Rubies and sapphires are widely considered to be among the most sought after and precious of gems. Together they account for over fifty percent of the world trade in colored gemstones. This book is the first from Richard Hughes on the subject, and the first major work to be devoted entirely to the corundum family of gemstones. It covers all aspects of rubies and sapphires, beginning with their history, chemical and physical properties. Other chapters look at treatments, synthetic corundums, methods of fashioning, famous rubies and sapphires, formation of corundum deposits and world sources, providing a valuable reference source for jewelers, gemologists, students, and the general reader.

Out-of-print. Click here to search for a copy

Short-wave fluorescent illumination provides a useful tool to spot curved banding in flame-fusion synthetic sapphire.

There are many benefits to using a long-wave UV torch when testing ruby and sapphire. Here are a few examples.

Experience the hidden world of ruby & sapphire in this exhibition with Lotus Gemology and Van Cleef & Arpels' L'École School of Jewelry Arts

Since the late 1960's, East Africa has been home to some of planet earth's greatest gem discoveries. And yet, little has been written about certain of these finds. In the autumn of 2007, the authors set out to fill in the gaps, specifically regarding Tanzania's Mahenge, Songea and Tunduru regions.

A discussion of the flux-healing treatment of rubies. This article was given the Richard T. Liddicoat Journalism Award by the American Gem Society in 2005.

A discussion of DRIFTS vs the Beam Condenser FTIR attachment in the testing of pink sapphire. The DRIFTS accessory is generally much better at unmasking heat treatment in ruby and sapphire.

Why should Hugh Hefner be the only one to enjoy twins? This special Hyperion Inclusion Gallery features images from the Lotus Gemology Hyperion Inclusion Database, but are shown as pairs, all the better to compare one form of beauty with another.

A discussion of how inclusion patterns mimic crystallographic symmetry in ruby and sapphire.

The ethics of gem enhancement disclosure.

Lotus Gemology's gemologists have lectured extensively about a wide variety of gemological topics including ruby, sapphire, jade, and more.