Investors pushed shares in Ashton Mining of Canada (ACA-T) down 38, or 20% of value, in late trading on Aug. 29, after the processing of a 10.7-tonne sample from the Renard 65 kimberlitic body in the Otish Mountains of Quebec, failed to return any large diamonds.
Earlier this summer, drill core from Renard 65 surrendered a 4-carat diamond. The exposed surfaces of the stone measure 8.8 by 8.2 by 4.8 mm. Ashton says the colourless octahedral composite crystal shows the potential of the Renard bodies for containing big-carat diamonds.
The latest sample, part of a 17.6-tonne, mini-bulk sample, run through the dense media separation plant returned an estimated diamond content of 23 carats per 100 tonnes (cpht). Included are 2.5 carats worth of diamonds exceeding 0.85 mm in at least one dimension.
In July, the first 6.95-tonne portion of the sample yielded an estimated diamond content of 34 cpht, and surrendered 2.35 carats of stones exceeding 0.85 mm.
Ashton says about 85% of the sample consisted of kimberlitic breccia with country rock xenolith ; the remainder is hypabyssal material.
On surface, Renard 65 measures about 1.5 ha in area. The pipe is one of 8 diamondiferous kimberlitic bodies discovered by Ashton and equal partner Soquem on the Foxtrot property in north-central Quebec.
So far, analysis of around 36 tonnes of material from Renard 2, 3, 4 and 65, all within a 0.5-sq.-km area (which also includes Renard 8 and 9) has returned some 20 carats of diamonds exceeding 0.85 mm. The four largest of stones, excluding the 4-carat stone, weigh in at 0.92, 0.77, 0.73 and 0.46 carats.
The partners plan a fall drill program on several of the bodies in anticipation of the collection of a bulk sample aimed at obtaining at least 100 carats. Meanwhile, a ground geophysical survey is testing several targets outlined by more than 700 indicator mineral samples.
Meanwhile, results from processing of an 8-tonne, mini-bulk sample from the diamondiferous Renard 1 kimberlitic, 300 metres north of Renard 65, are expected before year-end.