Quirks & Quarks

How to Make Diamonds in the Rough

Research into "cloudy" diamonds found in the Northwest Territories, and formed 200km underground, reveals briny inclusions with chemistry consistent with sea water.

Sea water may be a critical component in the formation of some diamonds

Fluid rich diamonds from the NWT. Some, like the example on the right, have gem diamond cores trapped within them. (Anetta Banas/University of Alberta)
The Northwest Territories are a diamond mine for ... well ... diamonds. But while many beautiful gems emerge from the NWT, Dr. Graham Pearson, a geophysicist and Canada Excellence Research Chair in Arctic Resources at the University of Alberta, is more interested in the ugly ones.

Along with gem-quality diamonds come cloudy, greenish stones, which contain inclusions of fluid trapped in the stones when they formed 200km beneath the surface. Dr. Pearson has identified the fluid as containing salts and other elements derived from seawater.

They suspect this material was cycled into the deep earth by tectonic activity, where the seawater became part of the raw material from which the diamonds crystallized.

Related Links

Paper in Nature
Release from the University of Alberta
Edmonton Journal story