BHP Billiton Diamonds has signed a long-term contract to supply rough diamonds to the Canadian jewelry manufacturer Corona Jewellery Company for its Maple Leaf Diamonds brand.

Corona Jewellery is the only Canadian manufacturer among the BHP Billiton Diamonds' 40 contract holders. BHP Billiton owns an 80% stake in the Ekati diamond mine in Canada's Northwest Territories, the most prolific diamond mine in North America, producing some 3% of all rough diamonds in the world by volume and 5% by value.

Retail Jeweller quoted Corona President John Minister calling a guaranteed regular supply of jewelry-quality Canadian diamonds "very impressive."

Minister noted that the company's customers had always demanded to know the origins of the diamonds used in its jewelry.