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Peregrine reports CH-7 bulk sample diamond grade of 0.88 carats per tonne

Published 12 January 2016

Peregrine Diamonds has reported that a 814.0 dry tonne bulk sample from the CH-7 kimberlite pipe on its 100% owned Chidliak Diamond Project in Nunavut, Canada, returned an overall diamond grade of 0.88 carats per tonne ("cpt").

A total of 717.65 carats of commercial-size (+1.18 mm) diamonds was recovered, including 53 diamonds one carat or larger and 183 diamonds over 0.50 carat in size. The largest gem quality diamond recovered was a 5.33 carat white/colourless octahedron with no inclusions. Significant diamond breakage was observed, as more fully described below, including a gem quality diamond that may have originally been larger than six carats. A substantial portion of the parcel is gem quality diamonds and a population of colored stones is present. Processing of the entire bulk sample was performed by the Saskatchewan Research Council ("the SRC").

An independent diamond valuation of the 717.65 carat parcel will be completed this quarter in Antwerp, Belgium by WWW International Diamond Consultants Ltd ("WWW").

Diamonds of special note described by the SRC include the following:

A 5.33 carat white-colourless transparent octahedron with no inclusions
A 5.02 carat off-white transparent octahedron with minor inclusions
A 4.40 carat off-white transparent macle with minor inclusions
A 2.01 ct white-colourless, transparent octahedron with no inclusions
Two yellow transparent octahedra, one at 0.52 carat, the other at 0.5 carat

Peregrine president and CEO Tom Peregoodoff said: "Once again the Peregrine team has delivered an excellent outcome. We are very excited with the results of the 2015 bulk sample from CH-7. These results continue to confirm the outstanding diamond resource potential of the Chidliak project.

"Transportation of the parcel to Antwerp is underway, and we look forward to the receipt of the diamond valuations, expected later this quarter. Preparation of the maiden CH-7 resource statement and revised CH-6 resource statement has commenced and we expect to complete this work in late March."

The entire bulk sample was processed by Dense Media Separation ("DMS") at the SRC, which is accredited to the ISO/IEC 17025 standard by the Standards Council of Canada as a testing laboratory for diamond analysis. Large-diameter reverse circulation ("RC") drill cuttings were screened during acquisition at Chidliak at a 1.13 mm square-mesh sieve where all material below 1.13 mm reported to the sump on site.

The SRC DMS processing facility is rated at five tonnes per hour and was outfitted with a 1.0 x 12 mm slotted feed preparation screen and a back-end high pressure grind roll ("HPGR") recrush circuit. Diamond recovery from concentrates proceeded through a twin stage X-ray sorting machine followed by a grease table finish and double-checked by hand sorting.

Diamond recoveries remained within normal parameters, with one notable exception: unusual grease-repellant coatings are present on diamonds from lateritized KIM-5 material therefore causing the diamonds to not stick to grease. Caustic fusion audits completed on KIM-5 grease table tailings returned 10.11 carats of diamond, largely in smaller size categories. Additional audits of the 2015 bulk sample materials are being considered.

As an element of Peregrine's Quality Assurance/Quality Control program, 266 laser-marked natural diamond tracers ranging in size from 0.09 to 1.62 carats were added to the bulk sample bags during sample collection, with 14 additional tracers inserted at the DMS processing facility. All 280 tracers were recovered as whole, unbroken stones during sorting at the SRC, a 100 percent recovery rate.

Source: Company Press Release