Investors bailed out of
The junior tabled disappointing results for eight widely spaced holes into the Sastre zone, which appear to have negated the bulk-tonnage potential for a large oxide gold resource. Sastre had been the most promising of the Tambor targets, returning the highest grades from the property. The zone was interpreted from detailed mapping, surface prospecting and hand trenching to extend some 500 metres along the face of a gentle ridge at an apparent thickness of 10 to 20 metres.
Radius initially zeroed in on Sastre after finding several old tunnels and pits in the area. A grab sample of float material taken from one of the pits ran 350 grams gold per tonne, while one of the adits averaged 4.9 grams over 12.8 metres. A dozen trenches dug into the side of the ridge returned consistent higher-grade results averaging 7-8 grams.
Radius tested a 600-metre length of the zone with eight reverse circulation holes totalling 565 metres. Five of the holes intersected the flat-lying mineralized zone in amphibolite-hosted wall rock, at or near surface, over thicknesses of up to 12.2 metres. These holes, however, returned low gold values and failed to repeat higher values obtained from trenches, adits and a 10-metre deep excavator pit, which averaged 9 grams over 7 metres. The best results came from hole 3, which cut 1.49 grams across 6.1 metres, starting at a depth of 18.3 metres.
The first hole hit the zone, but yielded no significant values, while hole 2 returned 1.3 grams over 3.1 metres, starting at a depth of 33.5 metres. Hole 5 returned a 1.5-metre intercept of 1.3 grams, while hole 6 returned 0.99 gram across 10.6 metres, starting at 16.8 metres from surface.
Hole 4, which was collared in the footwall of the zone about 50 metres southwest of the excavator pit, cut only 0.45 gram over 3.1 metres at a 9.1-metre depth. Holes 7 and 8 failed to extend the zone south of the Sastre adits.
The Sastre results, which were based on chips from reverse-circulation drilling, have left the management team scratching their heads over where the gold went, and puzzling over the geometry of the mineralized zone. Radius originally believed the zone dipped to the southwest at about 30 degrees, however, excavator trenching suggested that it was “crudely inclined” to the northeast.
Responding to speculation of supergene enrichment, Robert Wasylyshyn, vice-president of exploration, says no such evidence was seen in their “giant excavator slot,” which yielded “good grades” near the bottom of the 10-metre deep trench. He argues that some of the drilling was collared in the zone and therefore should have contained supergene gold, though the holes didn’t kick.
Another less likely explanation is the selective loss of gold by the RC hammer. This carries no weight with Wasylyshyn, who says they were drilling dry.
“We had every major and a number of analysts go there and re-sample all those pits and trenches,” says Wasylyshyn. “Everybody got within a 10 percentile agreement of our results. Gold Fields did a whole lot of due diligence sampling and gave us that database after we consummated the deal, and there are no glitches. The gold is reproducible; it wasn’t a one-time sampling effect.”
“We did the big stepouts, we didn’t hit it, so in the final analysis it couldn’t amount to much anyway,” says Wasylyshyn.
Radius has moved off the Sastre zone and is concentrating on a different meta-sediment rock package, which hosts both the Lupita and Bridge gold zones. “There we’re seeing a vastly different style of mineralization and bigger targets,” Wasylyshyn said.
Radius intersected wide intercepts of sulphide gold mineralization in the range of 0.8 to 2 grams within a carbonaceous phyllite unit while drilling the Lupita target. Results from the seven previously reported RC holes included 135.6 metres of 1.22 grams in hole 4, which ended in mineralization. Radius was RC-drilling below the water table at Lupita, so management decided to twin hole 4 with a HQ-diameter core hole to confirm grade distribution, as well as to test the lower limits of the zone. The core hole was lost at 90.5 metres and assay results remain pending.
The sulphide gold mineralization in the flat-lying, lithologically controlled, phyllite horizon occurs in association with strong multi-stage hydrothermal quartz veining containing disseminated pyrite and arsenopyrite. While constructing new access roads for drilling, Radius says it has uncovered altered and mineralized carbonaceous phyllite for some 500 metres west of hole 7, which cut 149.3 metres of 0.77 gram from surface.
This recessive weathering horizon has been traced for a further 3.5 km to the Bridge zone, where previous channel sampling averaged 3.59 grams over 85 metres.
Radius completed two holes at the Bridge zone before taking a two-week break from drilling. The holes intersected a thick sequence of carbonaceous black shale, with silica and minor sulphides. Assay results are expected shortly.
Drilling should have resumed on the Bridge zone at press time, to be followed by more core drilling for the Lupita zone. “There’s a big plum sitting in there and we want to know what makes it tick, so we will hit it with core as opposed to chips, and hopefully get some geology out of it,” says Wasylyshyn. Radius has completed 18 holes in 2,160 metres of drilling on three targets to date.
Wasylyshyn is also anxious to drill a series of targets in the Bella Vista area, 10 km west of Tambor. The company has outlined a parallel type of system that compares dimensionally and geologically to Tambor. Detailed mapping and sampling has returned strongly anomalous gold values from the 3-by-2.5-km San Pedro target area. Selected sampling of limited outcrop yielded values up to 7.5 grams over 12 metres and 8 grams across 10 metres. The company’s field crews continue to focus on hitting outcrops within a 20-km-long belt of geochemistry soil and rock.
Radius is sitting with $4 million in the bank and has 17.9 million shares outstanding.
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