Diamonds Reveals earth formation!

GIA scientist Dr. Karen Smit inks

Sulfur Isotopes in Diamonds!

Diamonds, long prized for their beauty and rarity, continue to reveal clues about the early history of our planet. To better understand how the most ancient continents came to be, researchers examined tiny mineral remnants trapped in diamonds during the formation of the earth.

The results were published in Science magazine, in the article Sulfur Isotopes in Diamonds Reveal Differences in Continent Construction by GIA (Gemological Institute of America) research scientist Karen Smit; Steven B. Shirey and the late Erik H. Hauri of the Department of Terrestrial Magnetism of the Carnegie Institution for Science; and Richard A. Stern, a research scientist at the University of Alberta.

“Diamonds are one of the most valuable gems, not only as jewelry but also in geoscience,” said GIA research scientist Dr. Karen Smit, the lead author of the recently published article in Science. 

“The mineral inclusions in diamonds let us study the inaccessible depths of Earth – somewhere that today’s science cannot otherwise reach.”

The researchers examined diamonds from the Zimmi mining area near the Libera-Sierra Leone border, which is known for producing yellow diamonds. 

The Zimmi diamonds are classified as Type Ib diamonds because they have rare nitrogen impurities. Type Ib diamonds are exceptionally rare in nature, accounting for less than 0.1% of natural diamonds mined worldwide.

By laser-cutting and polishing very thin plates from the Zimmi diamonds, the researchers were able to isolate and study sulphide inclusions, extracting chemical isotopes that offered clues to when the diamonds – and the deepest and oldest parts of the continents formed.

“This kind of insight is possible only because of the unique characteristics of diamonds,” said Dr. Wuyi Wang, GIA vice president of research and development. “GIA’s significant investment in research, unique access to rare diamonds and the outstanding collaboration with the Carnegie Institution and the University of Alberta made this significant discovery possible.” A summary of the Science article is available with GIA.