By Kip Keen (mineweb.com),
Best things come in small packages, they say, and for Sunridge Gold (TSX-V: SGV) at its Asmara project in Eritrea that seems to be the case with the latest resource upgrade of the Debarwa volcanogenic massive sulphide deposit.
It’s been three or so years since the last resource estimate, and while on the whole, little has changed size-wise for Sunridge at Debarwa, there now appears to be an intriguing high-grade sweetener worth considering as a small standalone mining project, Sunridge says.
First, though, there was a slight fizzle in terms of metal content in the upgrade as the amount of contained copper, gold and silver contracted ever so slightly, with only pounds zinc increasing. For comparison:
Debarwa Indicated 2008:
- 204 million pounds copper
- 219,800 ounces gold
- 3 million ounces silver
- 57 million pounds zinc
Debarwa Measured and Indicated 2011:
- 200 million pounds copper
- 180,000 ounces gold
- 2.9 million ounces silver
- 74 million pounds zinc
But, as they say, size, especially in mining where it equates with cost, doesn’t always matter. In upgrading Debarwa Sunridge honed in on a particularly high-grade portion of what was already the higher-grade supergene zone (read enriched by metals leached down from above).
Measured and indicated resources in the supergene are 1.4 million tonnes @ 5.15 percent copper, 0.07 percent zinc, 1.4 g/t gold and 33 g/t silver. Within that, however, there is what you might call a super-supergene zone, for which Sunridge had its consultants model size and grade within a plus-7.5 percent copper shell.
The result: 115,900 tonnes @ 16 percent copper translating into about 41 million pounds contained copper.
For Sunridge, this uber-copper zone, opens up an intriguing, if small, mining option. As it puts together a feasibility study looking at Debarwa on its own and as part of the three other deposits comprising the Asmara project, Sunridge says it will consider a scenario that fast-tracks the high-grade portion within the supergene zone to production and then ships a crushed feed directly to smelter “without the need for a concentrator.”
The point being, concentrators don’t come cheap and mining a low-tonnage high-grade deposit without one could speed the way to profits. Results from the feasibility study, due out by year’s end, will help flesh out that hypothesis.
