Mining Explorers 2009: Diavik Diamond Mines Inc.

(Rio Tinto plc. and Harry Winston Diamond Ltd.)

TSX: HW/NYSE: HWD/RTP:LON & NYSE

DDMI Manager Operational Readiness: Richard Storrie

DDMI Superintendent, Geotechnical Engineering:

Sarah Greer

DDMI Chief Geologist: David Eichenberg

The Diavik Diamond Mine is an unincorporated 60-40 joint venture between Diavik Diamond Mines Inc., a subsidiary of London-based Rio Tinto plc, and Harry Winston Diamond Mines Ltd., a subsidiary of Toronto-based Harry Winston Diamond Corp. Both companies have headquarters in Yellowknife, Northwest Territories. Diavik Diamond Mines manages the mine, which is rapidly moving toward underground production. Under the current mine plan for Diavik, diamond production from underground will begin in 2009 and continue beyond 2020. Open-pit mining, which began in 2003, is expected to cease in 2012. Diavik’s reserves are contained in three kimberlite pipes, A154 North, A154 South, and A418, located beneath the waters of Lac de Gras, just offshore of East Island in Northwest Territories. While small compared to the world average, these diamond ore bodies contain a higher-than-average content of readily marketable diamonds. The mine’s reserves are located on part of four mining leases, totaling less than two percent of Diavik’s mineral holdings. The JV is committed to searching for additional reserves on the remaining holdings, which cover nearly 240,000 hectares, or 578,400 acres. Through ongoing exploration, Diavik has discovered about 70 kimberlites on the claim block, about half of which are diamond bearing. In November 2008, Diavik’s production surpassed 50 million carats of rough diamonds. Total mine life remains 16 to 22 years, as projected in 1999 feasibility studies. Rio Tinto and Harry Winston have invested nearly US $800 million to build the underground mine.

The Diavik Mine is expected to mine 1.3 million metric tons of open pit ore in 2009, the majority of which will come from the A-418 kimberlite pipe, with the remaining production coming from the A-154 South open pit. Total carat production is expected to be between 5 and 6 million carats.

To extend production beyond 2022 at the mine, the partners hope to bring additional resources and exploratory tonnages into the reserves category.

On March 31, 2009, Kinross made a net investment of C$150 million to acquire roughly a 9 percent indirect interest in the Diavik Diamond Mine and a direct equity stake of about 22 percent in Harry Winston Diamond Mines. With the closing of the Kinross transaction, the Harry Winston economic interest in the Diavik Diamond Mine decreased to 31 percent. As of July 31, Harry Winston had unrestricted cash and cash equivalents of $67.9 million and working capital of C$296.6 million.

Rio Tinto, a multinational mining conglomerate, reported profits exceeding $2.6 billion in the second quarter of 2009, reflecting ample liquidity and resources. The company is traded on the London Stock Exchange.

P.O. Box 2498, Stn. Main

5007 - 50th Ave., Yellowknife, NT Canada X1A 2P8

Tel: 867-669-6500 • Fax: 867-669-9058

www.diavik.com