DIAMOND PAGE — K-14 diamond grade falls short

Diamond grades from the long-awaited processing of the K-14 bulk sample have proved disappointing for Ashton Mining of Canada (ACA-T).

A 479-tonne sample collected by reverse-circulation (RC) drilling from the kimberlite complex yielded a 56.45-carat parcel of stones, for an indicated grade of 11.78 carats per 100 tonnes (or 0.1178 carat per tonne). Only stones 1.2 mm or greater in size were recovered. The two largest stones weigh 0.9 and 0.88 carat each. Most of the diamonds are reported to be clear or greyish in color, though some are pale-brown and a few are yellow.

Ashton states: “The effective grade of 11.78 carats per 100 tonnes is considered disappointing, and indicates that kimberlite K-14 would be unlikely to support an economically viable mining operation.”

K-14 was considered the most promising of the 23 kimberlites discovered to date on the main Buffalo Hills option block in north-central Alberta.

Despite the K-14 results, Ashton says it remains encouraged by the overall prospectivity of northern Alberta. Sixteen of its kimberlites are diamond-bearing.

Ashton recently resumed drilling on the joint-venture Birch Mountain and Loon Lake properties, which surround the core Buffalo Hills block. Earlier this summer, airborne geophysical surveys were flown over extensive areas, following which detailed helicopter-borne surveys were flown over particular anomalies. Follow-up ground geophysics defined several promising drill targets. Also, an extensive sampling program for kimberlite indicator minerals was carried out in the summer.

The drilling is expected to be completed by mid-December.

In the meantime, a 17-tonne RC mini-bulk drill sample of kimberlite K-11 is being processed at Ashton’s North Vancouver laboratory. The K-11 kimberlite lies 30 km east of K-14. A previously reported RC hole into the kimberlite yielded 14 macrodiamonds and 106 micros from 189.5 kg of sample. The largest stone had a maximum dimension of 1.7 mm (a macro is defined as measuring greater than 0.5 mm in at least one dimension).

The Buffalo Hills project is a joint venture between Ashton, with 42.5%, Alberta Energy (AEC-T), with 42.5%, and Pure Gold Minerals (pug-t), with 15%.