After wrapping up a 37,000 metre drill program at Promontorio last year, the company was able to triple the resource to just over 36 million tonnes grading an average of 51.35 grams per tonne silver equivalent, for nearly 62 million measured and indicated ounces.
But while silver is in the spotlight at Promontorio, recent metallurgical testing has been evaluating the possibility of extracting a significant amount of gold from the ore, even though this was not factored into previous estimates.
If it proves viable, it could provide a noteworthy boost to project economics.
Preliminary metallurgical testing conducted by ALS Minerals out of Kamloops, British Columbia, on the gold component contained within the resource has already returned promising results.
Gold extraction tests using the post pressure oxidation technique achieved 94.5% recovery from the pyrite concentrate. An additional testwork is now underway.
The good preliminary results for gold recovery at Promontorio are especially encouraging given that one of the most promising, up and coming, exploration areas on the property has so far delivered great gold values.
The Dorotea zone, located to the north of the historic pit at Promontorio, has shown gold content higher than in the resource area and is a priority for the current exploration campaign.
Previous exploration at Dorotea indicated that the structure is mineralized along at least 1,000 meters of its length.
Highlights from drilling include 34.5 meters grading 1.73 grams per tonne gold, 74.83 grams per tonne silver and 2.4% lead and zinc as well as six meters grading 5.92 grams per tonne gold, 167.2 grams per tonne silver and 1.625% lead and zinc.
This year, the Kootenay team have put together another 30,000 metre drill program at Promontorio after raising C$8 million by private placement in November of 2012.
The focus of the program is on continuing to expand the known silver resource to the northeast and southwest of the main deposit, and on five adjacent, high-priority, mineralized stockwork breccia targets that offer significant potential for further resource expansion.
“The Dorotea zone, that yielded high gold numbers, will be a focus”, says Ken Berry, chairman of KootenaySilver.
“We did some limited drilling on Dorotea and it was very high in gold, silver, lead, and zinc. That was a major turning point to the recognition of Promontorio as a diatreme hosted system.”
In fact, that realization, that Promontorio is a diatreme hosted system, has significantly increased the blue sky potential.
This re-classification has identified Promontorio’s geology as consistent with many large and highly profitable deposits in a mineralised belt which runs right through Mexico and into the United States.
And some of the people who have been invited down to Mexico to examine Promontorio have begun to make comparisons to another very well known Mexican silver mine, Goldcorp’s Peñasquito mine.
Also a diatreme-hosted deposit, Peñasquito is the largest open pit mine in Mexico and in 2013 is likely to produce between 360,000 ounces and 400,000 ounces of gold, around 20 million ounces of silver, between 285 million and 305 million pounds of zinc, and between 45 million and 160 million pounds of lead.
At Promontorio, as is characteristic of diatreme deposits, it’s beginning to look like further high grade areas could be proven up in areas adjacent to the known resource, and additional metals such as gold could begin to play a more important role.
The Kootenay team has already reported results from the first eight holes drilled at Promontorio.
These holes were drilled in the Northeast Zone to search for extensions to the known mineralization, and the assays were certainly encouraging.
Highlights included 62 grams per tonne silver equivalent over 47 meters, 152 grams per tonne silver equivalent over five meters, and 119 grams per tonne silver equivalent over six meters.
If the initial results are an indication of things to come, the Kootenay team now have their long-held 100 million ounce target firmly in their sights.