Kennecott undeterred at Rockinghorse (May 27, 2002)

Spring drilling by Kennecott Canada Exploration on 12 exploration targets at the Rockinghorse joint venture in Nunavut’s emerging Coronation Gulf district failed to intersect any new kimberlites. However, several priority targets have yet to be tested.

Kennecott, a member of the Rio Tinto (RTP-N) group, is earning a 62.5% interest in the project from Tahera (TAH-T) by funding all costs up to a mine development decision. As part of the spring campaign, Kennecott further delineated the highly diamondiferous Anuri kimberlites with four core holes.

The Anuri and Anuri East kimberlites appear to coalesce in the upper region, with the shape of each suggesting a champagne glass. The upper part of the kimberlites have a surface expression measuring 180 metres north-south and 300 metres east-west, compared with an earlier estimate of 140 by 125 metres. The kimberlites have been intercepted to a depth of 200 metres. Further drilling will be required to test a possible northeast extension of the Anuri kimberlites.

Microdiamond results are available for the first hole drilled this spring, which crosscut the Anuri kimberlites from west to east. Collared near the centre of the Anuri kimberlite and aimed less than 50 toward the neighbouring Anuri East, the hole remained in kimberlite over a length of 254 metres, with the exception of the first 40 metres of lake sediments and overburden. A 228-kg sample from that hole returned 212 micros and 98 macros, including 17 stones larger than a 0.5-mm square mesh screen and two diamonds lying atop a 1-mm square mesh. The largest diamond recovered measured 2.21 by 2.1 by 1.69 mm.

These results compare favourably with previous microdiamond results from the Anuri kimberlites. Six-hundred micros and 337 macros were previously recovered from 656 kg of core sampled at Anuri. Sixty-one of the macros were larger than 0.5 mm in two dimensions, and nine of the stones exceeded 1 mm in two dimensions. The discovery hole into Anuri East yielded 75 micros and 34 macros from a 129.4-kg sample, including five diamonds greater than 0.5 mm in two dimensions and a single stone exceeding 1 mm square mesh.