Lytton and New Indigo release grade for Jericho

Partners Lytton Minerals (LTL-T) and New Indigo Resources (NDR-A) report that the average grade of the JD/OD-1 kimberlite pipe in the Northwest Territories is now 1.18 carats per tonne.

The announcement was made after a further 3,989 carats were recovered from the processing of 4,313 tonnes of an underground bulk sample from the land-based pipe, which is part of the Jericho diamond project. To date, 9,401 tonnes have been processed.

Testing of the JD/OD-1 pipe has shown that while the phases within the pipe vary in grade from 0.3 to 1.96 carats per tonne, the size distribution is broadly consistent. The largest diamond recovered weighs just over 40 carats, and the largest gem-quality diamond is 23.89 carats.

An appraisal of a 6,550-carat parcel recovered from the first 5,088 tonnes of processed kimberlite values the diamonds at an average US$61.71 per carat.

The partners note that an unusually high number of larger stones in the sample is an encouraging feature, and one which could materially influence future valuations.

The average value of stones below 10.8 carats was estimated at US$59.25 per carat. The appraisal was conducted by the Central Selling Organization.

Further processing of the remaining sample material from the 15,000-tonne underground bulk sample has been suspended. Lytton and New Indigo are confident the 9,401 tonnes processed to date have provided sufficient representative coverage of all phases within the pipe to enable operators to make a development decision.

A preliminary scoping study, which calls for initial mining of the higher-grade phases, suggests the JD/OD-1 pipe could support a 1,650-tonne-per-day mine, with a capital cost projected at $50 million.