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

A brief history of the heat treatment of ruby & sapphire, from ancient times to the modern era.

This article discussed the ruby and spinel mines of Afghanistan/Tajikistan, in an attempt to shed light on one of the great gemological enigmas.

The issue of gemological nomenclature is one that has been hotly debated for decades, because an attractive name is a crucial part of marketing and se...

A 1992 visit to Vietnam's Quy Chau ruby mines, the first by a foreign gemologist, along with commentary on US-Vietnam politics.

In 1991, titanium-diffused blue sapphires reappeared in the Bangkok market after an absence of many years. Touted as "deep diffusion," the stones prov...

This is what happens when someone who knows little about jewelry is asked to write something about jewelry. Richard Hughes tosses off a cheeky descrip...

Surface ('bulk') diffusion-treated corundums (SDTCs) created a stir in the Bangkok market in 1990. This article looks at the original patents and cont...

A discussion of brilliance, windows and extinction as they relate to the face-up appearance of colored gemstones. Diagrams demonstrate that extinction...

Probably the first opinion piece I ever wrote, it was my take on diamond grading from the standpoint of someone working with colored stones.