Rio Tinto executives pay visit to DDC.(DDC Facets)

A fresh wind blew in from Australia, via the Northwest Territories of Canada, arriving in the board room of the Diamond Dealers Club in December, when Keith Johnson, group executive director for Rio Tinto Diamonds; Nigel Jones, the company's general manager of marketing; and Joe Carrabba, the president of the Diavik diamond mine, came to meet the DDC directors and other key players in the New York diamond district.

Johnson told his hosts that Rio Tinto expects to supply $800 million worth or 10 percent of the world's rough, by value, next year when Diavik is fully on stream.

Antwerp is the center for Diavik's distribution, and the company has no plans at …