Vancouver — Results from
An 11-hole, 4,000-metre drill program focused on expanding the depth potential of gold mineralization met with limited success.
Drilling intersected vein-hosted gold mineralization in most holes, generally those 380-480 metres below surface, with one hole cutting mineralization at a depth of 511 metres. However, the mineralized intervals were generally narrow (averaging 0.3 to 0.7 metre in width) and grades ranged from about 1 to 17 grams gold per tonne, with most averaging 2 to 3 grams gold. A number of the mineralized intercepts returned significant silver and lead-zinc values.
The incidence of multiple mineralized vein intercepts at depth, in all but one hole, significantly expands the size potential of the mesothermal vein system. However, the apparent challenge is to develop larger, profitably extractable blocks of higher-grade gold mineralized material in the sub-parallel vein system.
The company says that drilling does not always provide a representative sample of actual mineralization in the Gralheira vein system.
St. Elias geological consultant John Brophy says, “the tenor of assays obtained from core in the deep-drilling program is consistent with earlier results from shallow drilling.”
He adds that it has been demonstrated, based on underground bulk sampling from the 350-metre-long adit situated in the central portion of the property, that the grades and widths of mineralized intercepts derived from drill holes understate the grade and tonnage potential of the mineralized zone.
“If bulk sampling of the mineralization at these depths were to be undertaken, it could reasonably be expected that the tenor of the deep-seated mineralization encountered in the recent drill program could increase accordingly,” explains Brophy.
Previous drilling by the company targeted near-surface gold mineralization to a depth of 200 metres along 2 km of strike at Gralheira.
The property covers almost 17 sq. km and hosts the past-producing Jales mine, as well as the Gralheira gold deposit, located about 700 metres north. Jales, which ceased operations in 1992, produced about 830,000 oz. gold from material grading 12.9 grams per tonne.
Gold occurs within an extensively mineralized, 3-km shear zone with a number of sub-parallel veinlets and veins ranging from 0.5 to 1.5 metres in width. Both deposits were historically mined by the Romans: Jales to a depth of more than 600 metres, and Gralheira produced from depths approaching 200 metres and along a strike length of 2 km.
Previous exploration included an extensive drill campaign by
A Cogema 1997 pre-evaluation study on Gralheira, reviewed an historical (before the days of National Instrument 43-101) 200,000 oz. gold resource, along with metallurgical testing on bulk samples showing gold recoveries of more than 90% using flotation.
St. Elias is earning a 51% interest in the project from
Following the release of the deep-drill results, shares of both St. Elias and Kernow both dropped precipitously, shedding more than 50% of their value over a couple of trading days. A subsequent clarification release by St. Elias, reviewing the assay procedure for the samples and the incurred delays, seemed to calm fleeing shareholders, with both stocks recovering significantly. Shares of St. Elias recovered to 61, after dropping to a low of 36 apiece following the assay results, and Kernow shares bounced back to 24, following a drop to 16.
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