Lotus • Articles from Lotus Gemology

Discussion of gem treatment disclosure and its somewhat difficult history.

This article discusses the challenges of identifying inclusions based on observation alone. While certain features can help narrow down the possibilities, other methods such as micro Raman help identify inclusions with a greater degree of certainty.

A discussion of the literature of ruby and sapphire (corundum), with particular emphasis on the most collectible books covering ruby and sapphire around the world.

The story of Richard Hughes' four-decade adventure with jade, from Burma's jadeite mines to China's classic mutton-fat nephrite deposit at Hetian, Xinjiang Province. The work of China's modern jade carving masters is also discussed.

A large black star sapphire was brought in for testing. Two large pits on the base were carefully filled with brown dopping varnish. After removal of the varnish with alcohol, it was found that a large portion of the base had been filled with a lead glass.

This article discusses the use of handheld long-wave ultraviolet torches with the microscope. It has been found that these have tremendous utility in identifying and characterizing certain oiled gemstones, such as emerald, tourmaline, etc.

The word "jade" often evokes the green jadeite used in jewelry. However, some of the most valuable jade in China is not this green jadeite, but in the creamy "mutton fat" carved nephrite from Hetian, Xinjiang province. In the past, many carvings touched upon familiar motifs like dragons or religious symbols, while in recent decades there has been a revolution of carving, with artists incorporating modern themes and styles into their work. Lin Tze-Chuan, an influential collector and patron of many jade carvers, is considered by many to be the father of Chinese contemporary jade carving. Here he discusses the changing world of jade carving and what he looks for when commissioning new work.

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.

The world sapphire market has changed dramatically in the past 40 years. The authors review the famous sources of the past and look at the current situation in sapphire around the globe.

This excerpt from Ruby & Sapphire: A Gemologist's Guide (2017) details the ruby and sapphire deposits of Madagascar. Since the mid-1990s, Madagascar has become one of the world's most important sources.