TORONTO (miningweekly.com) – Quebec-based project developer Stornoway Diamond has recovered 962.8 ct of diamonds from the Renard 65 bulk sample it collected at its fully owned Renard project, in north-central Quebec.

In total, 962.8 carats of diamonds larger than 0.85 mm (a +1 Diamond Trading Company size sieve) were recovered from 5080.8 dry tons.

Stornoway said the size of the diamond sample recovered and the incidences of large diamonds were consistent with its expectations for the Renard 65 kimberlite at the sample location.

The objective of the Renard 65 bulk sample was to collect about 1 000 ct of diamonds for valuation in Antwerp, Belgium, which the company expected to take place soon.

The largest diamond recovered from the sample was a 9.78 ct white octahedral gem with a preliminary valuation of $7 000/ct. The next-largest diamond was a 6.41 ct white gem, also of high quality, with a preliminary valuation of $4 700/ct.

The Renard 65 bulk sampling was undertaken with the aim of testing the potential conversion of National Instrument 43-101-compliant inferred material to an indicated resource and possibly to a mineral reserve for inclusion in the project's mine plan.

Renard 65 currently contains an inferred resource of 3.7-million carats, held within 12.9-million tons grading 29 ct per hundred tons (cpht) to a depth of 290 m, with an exploration potential estimated at between 6.8-million carats and 13.7-million carats from depths of between 290 m to 775 m.

The current bulk sample was extracted from a site that is known to represent a lower-grade portion of the kimberlite, but which was easily accessible from surface. In 2008, a 266 t trench sample from the same location returned 51.8 ct for a diamond recovery of 19 cpht, which Stornoway said was looking to be identical to the current result.

Stornoway in January said it had reduced the estimated capital cost of its Renard diamond project by C$50-million to C$752-million.

This followed the completion of a new mine design and cost optimisation exercise for the project.