Cristal bulk sample yields 96 commercial stones

The results from the balance of a 100-tonne bulk sample derived from Pele Mountain Resources‘ (YPN-V) Cristal showing, one of several on the Festival property near Wawa, Ont., are in.

The Canadian exploration division of De Beers, now a subsidiary of Anglo American (AAUK-Q), has recovered another 66 diamonds weighing in at 1.77 carats. The largest stone weighs 0.18 carats.

In December, the company reported that about 25% of the concentrate from the bulk sample surrendered 29 diamonds weighing 0.54 carat. The largest stone from that portion of the bulk sample weighs 0.07 carat.

The bulk sample was taken last September from an outcrop of diamond-bearing, pyroclastic ultramafic breccia near the centre of the showing. The breccia facies makes up the base of the unit, and the pyroclastics represent the top, with ash tuffs increasing in proportion toward the upper contact. The showing is at least 200 metres wide.

Surface sampling of all facies of the Cristal prospect has indicated that the unit is diamondiferous. Fifteen samples weighing a total of 171.3 kg yielded 327 microdiamonds from all size fractions up to and including 0.6 mm square mesh (a micro is 0.5 mm in at least one dimension). At least 10 stones exceed 0.5 mm in one dimension. The best results have come from samples taken near the contact between the pyroclastics and more brecciated material. Three samples, weighing a combined 39.4 kg, returned 159 micros. The 100-tonne bulk test sample was collected in the immediate area of these samples, from a 10-by-10-metre section.

Modeling of the sample location by De Beers forecasts a “total content model” at a grade of 6 carats per hundred tonnes, down to a 1 mm square mesh cut off. The model makes use of only the largest size classes for the macrodiamonds. The model suggests that a larger sample from the site will recover larger diamonds.

Independent consultant Edward Walker says the recovery of 96 commercial size diamonds confirms the existence of a macro diamond population in the approximately 2.7 billion year old volcanoes. Given the high tonnage potential and outstanding infrastructure, coupled with the presence of commercial size and clear well preserved diamonds, as previously reported by Pele, in my opinion there is a strong potential for an economic diamond deposit at Pele’s Festival Property.”