DIAMOND PAGE — New discoveries yield more diamonds at Diavik, Camsell Lake

Diavik Diamond Mines, a division of Rio Tinto (RTP-N), and its parter, Aber Resources (ABZ-T), have begun a final feasibility study on four diamond-bearing kimberlite pipes at the Diavik diamond project near Lac de Gras in the Northwest Territories. The study is intended to determine the capital cost of building a mine.

The four pipes under review are A-154 South, A-418, A-154 South and A-21.

In 1997, exploration drilling at the project uncovered three new kimberlite pipes — A-11 North, A-840 and T-107.

To date, 50 kimberlite pipes have been found on the property, 20 of which were found to be diamondiferous. Diavik Diamond, the operator, holds a 60% interest in the Diavik project. Aber Resources (abz-t) holds a 40% participating interest.

The exploration budget for Diavik in 1997 was $3.1 million. More than 80 anomalies were tested with ground geophysics, 26 of which were drilled.

A 452.2-kg sample, recovered from three holes drilled into the A-11 North kimberlite, returned 117 macrodiamonds and 206 micros (a macrodiamond is defined as measuring greater than 0.55 mm in at least one direction).

Further results from three additional holes at A-11 North are pending, as are results from the A-840 and T-107 discoveries.

A-11 North is a land-based pipe, situated 8 km southeast of the A-418 and A-154 pipes.

Early in 1997, a geophysical anomaly was defined along the property boundary with BHP Diamonds and Dia Met Minerals (DMM-T). Two drill holes have confirmed the anomaly to be a diamondiferous kimberlite pipe, which appears to be largely on the BHP-Dia Met side of the boundary. An exploration program for next year is being discussed.

A $1.4-million, 40,000-line-km airborne survey (75-metre line spacing) was completed during the fall over most of the 569,266-acre property.

For 1998, $5 million is budgeted for exploration. The work will include follow-up work of anomalies from this airborne program, as well as mini-bulk sampling of the A-11 North pipe using large-diameter core drilling.

Farther south, at the Camsell Lake project, Winspear Resources (WSP-V) has received results from caustic fusion analysis on material collected from a boulder train discovered on the southern shore of Snap Lake. The train consists mostly of kimberlite breccia boulders measuring up to 25 cm in length.

In total, 169 macros and 325 micros were recovered from 214.13 kg of material collected from four sample sites in the boulder train. Eighteen of the macros measured between 1 and 2 mm in size, four of the stones were between 2 and 3 mm, and three were between 3 and 4 mm. The largest diamond recovered measured 3.475 mm in its longest dimension and is described as a white, translucent octahedron.

Winspear says the size of the boulders and their angular shape are consistent with a nearby source, which, field evidence suggests, is in Snap Lake.

Winspear is operator of the Camsell Lake project and holds a 57.3% interest.

Aber maintains a 42.7% interest. Details of a winter-spring program have yet to be announced, but Winspear anticipates that a significant work program will be carried out in the Snap Lake area beginning in late January or early February 1998.