- 96.7 g/t gold over 2.2 metres and 29.3 g/t over 5.2 metres in hole WST-21-0824;
- 49.9 g/t gold over 4 metres in OSK-W-21-2503-W1;
- 97.4 g/t gold over 2 metres in OSK-W-21-2512-W1;
- 69.9 g/t gold over 2.4 metres in OSK-W-21-2522;
- 67.0 g/t gold over 2.1 metres in WST-21-1891;
- 28.7 g/t gold over 4.1 metres in WST-21-0797A; and
- 51.9 g/t gold over 2.2 metres in OSK-W-21-2512.
Saying the infill program at Windfall continues to deliver “positive” results may well be an understatement. Osisko has already estimated the deposit to contain 6 million measured and indicated tonnes at 9.6 g/t gold, containing 1.9 million oz. and 16.4 million inferred tonnes at 8 g/t gold, containing 4.2 million oz.
The preliminary economic assessment for the project posits an after-tax net present value of C$1.5 billion and an after-tax internal rate of return of 39.3%. The after-tax payback period would be only 2.2 years.
Windfall is expected to produce 300,000 oz. of gold from ore with a diluted grade of 8.1 g/t gold annually for the first seven years of commercial production. The mill has a planned capacity of 3,100 t/d with gold recovery of 94.8%. The preproduction capex would be C$544 million including construction of a power line and a C$55 million contingency.
(This article first appeared in the Canadian Mining Journal)
