Mountain Province, De Beers launch Gahcho Kue Feasibility Study

September 02, 2009

TORONTO (miningweekly.com) – A feasibility study is now under way on the Gahcho Kue
diamond prospect, in Canada's Northwest Territories, Mountain Province Diamonds said on
Tuesday.

Gahcho Kue is 51% owned by De Beers Canada and 49% by TSX- and Amex-listed Mountain Province.

JDS Energy and Mining Inc. has been hired to do the study, which is expected to take about 12
months and cost C$10-million.

"JDS and our joint venture partner, De Beers Canada, have considerable experience in
Canada's diamond industry. This ensures that the Feasibility Study will identify the optimal
development options for the Gahcho Kue project," commented Mountain Province CEO Patrick
Evans.

In July, De Beers Canada and Mountain Province agreed to revise their joint venture on
Gahcho Kue.

De Beers had been sole funding work on the project, as part of an earn-in agreement, but the
ownership split will now stay at current levels, and the partners will fund their respective share
of spending.

Mountain Province also agreed to repay its proportionate share of historical spending on the
project, which has been calculated at C$120-million.

The C$59-million payment will be made in several stages and forms, one of which includes
Mountain Province funding De Beers' share of the costs to complete a feasibility study on the
project.

The Gahcho Kue project consists of a cluster of kimberlites, three of which have an indicated
resource of approximately 30,2-million tons, grading at 1,67 ct/t, (approximately 50,5-million
carats), plus an inferred resource of about 6-million tons, at 1,73 ct/t, or around 10,3-million
carats.