In 1983, the Argyle mine was established as the first major diamond-mining operation in Australia. Almost immediately, it became the world’s largest source of diamonds in terms of the volume (carats) produced. The discovery, development, and operation of this mine challenged conventional beliefs about diamond geology, mineral processing, and the marketing of gem diamonds. In its peak year, 1994, the mine produced over 42 million carats (Mct) of rough diamonds, which represented 40% of the world’s production. A large proportion of this staggering output consists of small brown-to-yellow—as well as some near-colorless and colorless—rough diamonds. A major cutting industry developed in India to process these diamonds into cut gems. The Argyle mine is also noted for the production of a very limited amount of rare pink diamonds.

About the Authors: James Shigley is director of GIA Research in Carlsbad, California. John Chapman is an independent diamond scientist, and Robyn Ellison is a senior business analyst for Argyle Diamond Sales Pty. Ltd., both in Perth, Australia.