DIAMOND PAGE — Partners await valuations from AK

A mini-bulk drill sample collected this past winter from the 5034 kimberlite pipe on the AK property in the Northwest Territories has returned results consistent with previous work.

Monopros, a subsidiary of De Beers Consolidated Mines (DBRS-Q), recovered 101 carats of diamonds from a 55.8-tonne bulk sample, for an overall grade of 1.81 carats. The mini-bulk sample, like those recently reported for the Hearne, Tuzo and Tesla pipes, was extracted using reverse-circulation drills. A 1-mm square screen size was used as the bottom cutoff size. Five of the diamonds weighed greater than 0.8 carat, with the two largest weighing 1.9 and 1.69 carats.

Monopros can earn up to a 60% interest in the AK-CJ properties, held 90% by Mountain Province Mining (MPV-V) and 10% by Camphor Ventures (CFV-V). The 5034 kimberlite is the original discovery in the cluster of four pipes.

Earlier work on the 5034 had determined a grade of 2.4 carats per tonne, based on a 250-carat parcel of stones recovered from a 104-tonne mini-bulk core sample. However, no bottom cutoff size was used, and De Beers later revised that grade to 1.5 carats per tonne using a commercial cutoff screen size of 1.65 by 1.65 mm. The loose stones were valued at US$55 per carat.

The 5034 kimberlite is estimated by De Beers to contain a 15-million-tonne resource down to a depth of 300 metres.

This past winter, in an attempt to determine preliminary grades and valuations, Monopros collected 50-tonne mini-bulk samples from each of the 5034, Hearne, Tuzo and Tesla pipes. A summary of the results from the pipes other than 5034 are as follows:

* The Hearne pipe was determined to have a grade of 3.28 carats per tonne, based on a recovery of 205 carats of diamonds from a 62.6-tonne sample; * The Tuzo pipe has an indicated grade of 2.24 carats per tonne, based on the recovery of 108 carats from a 48-tonne sample; and

* The Tesla pipe grades 0.43 carat, based on the recovery of 25.9 carats from a 60-tonne sample.

The four pipes are believed to contain a combined resource of 30-40 million tonnes, projected to a depth of 300 metres.

The recovered parcels from all four pipes are being sent to Kimberly, South Africa, for initial evaluation. A formal decision on whether to advance the project to a major bulk-sampling stage will be made once all the results are received and analyzed.

“Monopros and the company are pleased with the results, which are consistent with the modeled grade obtained by De Beers,” Mountain Province states in a news release. “Both Monopros and the company believe that with very good results for the four pipes now in, the project should advance to the bulk-sampling stage,”

In a recent report, Canaccord Capital analyst David James says the bulk-sampling program may entail recovering 1,000-2,000 carats from each pipe using a 12-inch drill and on-site recovery plant at an estimated cost of $10 million.