THE DIAMOND PAGE — Bulk sample under way at Jericho project

At the Jericho project in the Northwest Territories, diamond explorers Lytton Minerals (LTL-T) and New Indigo Resources (NDR-A) have begun processing a bulk sample of the land-based JD/OD-1 kimberlite pipe.

The partners have set up a pilot test plant at Echo Bay Mines’ (ECO-T) Lupin gold mine, 20 km to the south. The plant will process 4,000 tonnes per month.

In 1996, the companies extracted some 15,000 tonnes from the pipe via a 275-metre-long decline, driven to a depth of 75 metres. The results will form the basis of a feasibility study.

The pipe is estimated to contain 15 million tonnes to a depth of 750 metres.

A 95.4-tonne mini-bulk drill sample yielded 1.46 carats per tonne for diamonds greater than 1 mm in one dimension, and 1.03 carats for those greater than 2 mm.

Early valuations averaged US$95 per carat for diamonds greater than 2 mm.

The JD/OD-1 is one of three diamondiferous pipes identified to date on the project. It and the JD/OD-2 pipe were discovered in early 1995, within a short distance of one another. Similar mineralogy leads the companies to speculate the pipes may be connected. JD/OD-2 is a land-based pipe as well.

The partners discovered a third pipe last summer, 7 km west of JD/OD-1 and JD/OD-2. Initial sampling confirmed the pipe was diamondiferous.

In related news, Kennecott Canada has entered into a joint-venture option agreement with Lytton and New Indigo to earn up to a 50% interest in claims comprising 3 million acres in the Northwest Territories.

The claim package includes Lytton’s wholly owned ICE property, covering the Ranch Lake and T31 diamondiferous pipes. The Jericho project and about 1 million acres of surrounding claims are not included in this joint venture.

Kennecott can initially earn a 25% interest by incurring $25 million of exploration expenditures over six years, or a half interest by spending a minimum of $50 million on exploration and feasibility.

Kennecott will initially focus on selected areas where previous sampling delineated indicator mineral dispersion trains. As well, further evaluation of the Ranch Lake pipe is planned.

A previous, 28.45-tonne drill sample from the pipe yielded 112 diamonds weighing 5.384 carats for a preliminary grade of 0.189 carat per tonne. Ranch Lake is estimated to contain 57 million tonnes of kimberlite to a depth of 300 metres.