De Beers and Mountain Province Diamonds Report On the Diamonds Recovered From the 2002 Bulk Sample of the 5034 Diamond Pipe; Large Diamonds Recovered.

Business Editors

ONTARIO, Calif.--(BUSINESS WIRE)--Sept. 4, 2002

Mountain Province Diamonds Inc., (OTCBB:MPVI)(TSE:MPV) announced that it has been notified by its joint-venture partner De Beers Canada Exploration Inc. (De Beers Canada), a wholly owned subsidiary of De Beers Consolidated Mines Ltd. (De Beers), that the diamond recovery from the sample concentrates of the kimberlite recovered from the 2002 bulk sample of the western and central lobes of the 5034 pipe has been completed in Johannesburg, South Africa.

A total of 1,215 carats were recovered with the three largest diamonds weighing 7.0, 6.6 and 5.9 carats. A significantly larger number of diamonds greater than one carat were recovered this year compared with the bulk samples of 1999 and 2001 (70 compared with 42 and 34 respectively).

The west and center lobes of the 5034 pipe are now seen to have a larger proportion of diamonds greater than half a carat than the east lobe, sampled in previous years. The number of diamonds available (especially larger diamonds) for valuation has as a result increased and should lead to more confidence in the value per carat modeling.

The diamonds will be sent to the Diamond Trading Co. (DTC) in London, for valuation. The 5034 kimberlite pipe is one of the largest and has one of the highest values of the five diamondiferous bodies in the cluster at Kennady Lake, located on the joint-venture's AK claims in the Northwest Territories of Canada.

As was mentioned in the April 24, 2002 news release, De Beers completed the winter 2002 bulk sample program of the 5034 and Hearne pipes on April 20, 2002. The purpose of the bulk sampling program is to increase the available revenue information for these two pipes.

Since revenue is determined by grade and diamond value, and since the two kimberlite pipes contain internal zones that vary in grade, it is important to combine diamond grade estimates along with diamond revenue estimates. The large number of diamonds obtained in the 2002 program will thus increase the confidence in, and accuracy of, revenue modeling via an enhanced understanding of grade, diamond size and frequency distributions and diamond values.

Last year, De Beers observed that a population of high-quality, top color diamonds exists amongst the diamonds recovered from the 2001 bulk sample. Specifically, the 9.9-carat diamond recovered from the 5034 pipe is such a diamond and was valued at US $60,000.

These high-quality, top color diamonds have a significant impact, especially the larger ones, on the revenue per tonne so the more accurately their frequency of occurrence is known, the greater the confidence in and accuracy of the revenue per carat modeling.

A total of six large diameter holes, consisting of two clusters of three holes, were drilled in the center and west lobes of the 5034 pipe. The 5034 pipe consists of four lobes: east, center, west and north with the first three being approximately the same size and having an estimated indicated resource to 300 m depth of 2.52, 2.85 and 2.74 million tonnes of kimberlite respectively.

The same drill (24-inch diameter) and the same drill method (a "diamond friendly" flood reverse system) that was used last year were used again this year. In the 1999 bulk sample, a reverse circulation drill with a diameter of 12.25 inches was used.

   Drill Hole          Tonnes       Carats       Grade (ct/tonne)

West Lobe 2002-88      191.7        419.5             2.19
West Lobe 2002-89      143.4        243.6             1.70
West Lobe 2002-102     101.9        179.9             1.77
West Lobe 1999-03       49.9         92.6             1.86

Center Lobe 2002-81    138.5        138.2             1.00
Center Lobe 2002-86    139.7        109.9             0.79
Center Lobe 2002-90    121.0        123.8             1.02
Center Lobe 1999-06     42.2         38.5             0.91
Center Lobe 1999-05     45.7         60.02            1.32

De Beers recovered a total of 1,215 carats from 836 tonnes of kimberlite. The results for each drill hole are shown in the table. The Dec. 14, 1999 news release presented the modeled grades for each lobe of the 5034 pipe; 1.85, 1.30, 1.70 and 1.70 carats per tonne for the west, center, east and north lobes, respectively.

The three holes drilled into the west lobe (holes 2002-88, 2002-89 and 2002-102) were located from 7 to 12 m to the south of the 1999 drill hole 1999-03 and were separated by approximately 6.5 m from each other. The average grade of the three 2002 holes is 1.93 carats per tonne.

The center lobe has a lower grade than the other lobes, partly due to a lower grade zone in part of the western half of the lobe. The three holes (2002-81, 2002-86 and 2002-90) were drilled from 5 to 11 m from hole 1999-05 and from 9 to 16 m from hole 1999-06 and were spaced from 6 to 7 m apart.

De Beers decided to drill in this part of the pipe to get a better handle on grade estimates for this lower grade zone. The average grade of the three 2002 holes is 0.93 carats per tonne, which is slightly higher than that found in hole 1999-06 but not as high as in hole 1999-05.

Bulk Sample    Location      Carats       Number of
   Year        in 5034                    diamonds
               (Lobe)                     greater
                                          than 2
                                          carats

   2002        west and       1,215       21
               center

   2001        east             914       10


   1999        half east,     1,005       10
               west and
               center

Bulk Sample    Number of      Number of   Five largest
   Year        diamonds       diamonds    diamonds
               greater        between     (carats)
               than 1         0.5 and
               carat(a)       1 carat

   2002        70             161         7.0, 6.6, 5.9,
                                          4.6, 4.6

   2001        34             104         9.9, 4.5, 2.6,
                                          2.5, 2.4

   1999        42             113         10.0, 4.90,
                                          4.85, 3.9, 3.8

(a) Includes those diamonds over 2 carats.

The number of diamonds recovered in three different size ranges (between 0.5 and 1 carat, greater than 1 carat, and greater than 2 carats) is shown in the table for all three bulk samples. In total, for the 2002 bulk sample, there are 70 diamonds weighing more than 1 carat, which include 21 greater than 2 carats, and 161 diamonds between half a carat and 1 carat.

The number of diamonds recovered in all three size ranges this year is proportionately (to the total number of carats recovered) significantly greater than those diamonds recovered in 1999 and 2001. The diamonds recovered from the 5034 pipe in 2001 were all from the east lobe and in 1999 nearly half were from the east lobe.

More specifically, when comparing the ratios of the number of diamonds in each of the three size ranges to the total number of carats recovered per lobe for the diamonds recovered in 2002 in the west and center lobes, with those diamonds recovered in the east lobe in 1999 and 2001, it can clearly be seen that the west and center lobes have a larger proportion of diamonds greater than half a carat than the east lobe.

Furthermore, the number of diamonds recovered in 2002, in each of the three size ranges, for the center and west lobes are proportionately (to the total number of carats recovered in each lobe) very similar: 6 and 15 greater than 2 carats, 21 and 49 greater than 1 carat and 50 and 111 between half a carat and a carat, respectively.

The number of diamonds available, especially the greater number of larger diamonds, for valuation has now increased and should lead to more confidence in the value per carat modeling. The diamonds will be sent to the Diamond Trading Co. (DTC) in London, for valuation. After that, revenue per tonne modeling, taking into account both the updated grade information and the diamond values, will be performed in Johannesburg.

Jan W. Vandersande Ph.D., president and CEO stated: "We are very pleased with the results. The increase in the number of larger diamonds recovered compared to 1999 and 2001 will hopefully positively impact the size-frequency curves and thus the modeled values."

The results from the bulk sample of the Hearne pipe are expected in several weeks.

Mountain Province Diamonds is a diamond exploration and development company. The AK claims, located in the Northwest Territories of Canada are now held 44.1% by Mountain Province Diamonds, 4.9% by Camphor Ventures (CDNX:CFV), and 51% by De Beers Canada Exploration Inc.

As reported in its news release on March 7, 1997, Mountain Province Diamonds and its partner entered into a joint agreement with De Beers Canada Exploration formerly known as Monopros Ltd. (a wholly owned subsidiary of De Beers Consolidated Mines Ltd.) under which De Beers Canada Exploration has the right to earn up to a 60% interest in the AK property by taking the project to commercial production.

This release may contain forward-looking statements, within the meaning of the "safe-harbor" provision of the Private Securities Litigation Reform Act of 1995, regarding the company's business or financial condition. Actual results could differ materially from those described in this news release as a result of numerous factors, some of which are outside of the control of the company.