QUEBEC – Montreal’s Aurvista Gold Corp
. says preliminary metallurgical testing has recovered 92% of the gold from samples taken at the Douay gold project 50 km southwest of Matagami.
[caption id="attachment_1003717640" align="alignleft" width="300"] Core from the Douay project in the Abitibi Greenstone Belt frequently contains visible gold.
The average gold grade of the sample composites was 1.89 g/t gold. The samples also contained about 1.50% sulphur. Gravity and flotation were tested in series. About 26% of the gold reported to the gravity circuit, and an additional 66% was recovered by flotation. The tests indicated a strong correlation between gold recovery and sulphur recovery.
To understand the relationship between gold and sulphur in the samples, a similar series of tests was run but with the addition of cyanide leaching to treat the flotation concentrate. Average recovery in this case was 85%. If samples from the Northwest zone were excluded from these tests, the average gold extraction was 88.9%. The Northwest zone samples came from felsic volcanic rocks, whereas the other samples came from mafic volcanic and porphyry host rocks.
Aurvista expects that using a gravity-flotation-leaching flowsheet would result in capital and operating cost advantages over leaching whole ore, especially as the leach circuit would be one-tenth the size if flotation concentrate is treated.
Learn about the Douay gold project at www.AurvistaGold.com.