French Blue diamond is explored in Gems & Gemology’s Spring issue

For the Spring 2009 issue of its Gems & Gemology publication, the Gemological Institute of America (GIA) has given a concentrated and in-depth editorial on the French Blue diamond, a rare piece which which disappeared in 1792 during the French Revolution. It has long been believed that the 45.5 ct Hope diamond was cut from the 69 ct French Blue. A lead cast of the fabled French Blue recently discovered at the Muséum National d’Histoire Naturelle (MNHN) in Paris appears to validate this theory. In “The French Blue and the Hope,” Dr. François Farges of MNHN and coauthors used the cast to create a computer model that sheds new light on the Hope-French Blue connection.

“This article reconstructs the history of the French Blue and offers implications for its fate,” says G&G Editor-in-Chief Alice Keller. “It's a significant breakthrough in our understanding of this mythic diamond and the famous stone cut from it,” she added.

The publication also features rare coloured diamonds from Australia's Argyle mine, in “Gray-to-Blue-to-Violet Hydrogen-Rich Diamonds from the Argyle Mine, Australia. ” In this piece, Dr. Carolyn van der Bogert leads an investigation of the gemological and spectroscopic features associated with this rare color group. These features can separate Argyle diamonds from goods of similar color that may be treated or synthetic.

The issue also touches on the topic of the cause of pink zones in copper-bearing tourmalines from Mozambique, exploring hackmanite/sodalite from Myanmar and Afghanistan, radioactive solution-related pink zones in blue to blue-green copper-bearing tourmalines from Mozambique, and the identification of endangered pink-to-red Stylaster coral by Raman spectroscopy. A pleasant read is also a special feature announcing this year's Dr. Edward J. Gübelin Most Valuable Article Award winners.