RE:RE:RE:RE:RE:RE:RE:RE:RE:Yes WG The following is from a 16 Sept; 2016 news release on bulk mining at BC. Please note that the strip ratio was 2.5 to 1 and the cost to deliver a ton of ore to the crusher was less than $10 per ton. What we don't know is how much the costs increase with a strip ratio of 8.43 to 1 and the cost of trucking the ore to the mill::
Results of Bulk Sampling
Over a three week period beginning in late July, Novo extracted approximately 30,000 tonnes of mineralized conglomerate from a pit in the central part of the Beatons Creek oxide resource. Most of the material came from one conglomerate horizon (“reef”); however, about 500 tonnes were extracted from a second reef about two meters stratigraphically below. Although the initial plan was to extract 10,000 tonnes of reef from each of three pits, it was recognized that grade blocks in the reef that was mined displayed a similar range, 1.5-5.0 gpt, to that expected from the three pits, 1.9-5.0 gpt. Therefore, Novo considers the material that was extracted to be similarly representative. By taking sample from one pit, extraction took three weeks rather than the planned six, and costs were significantly reduced.
Results of trial bulk sampling were very encouraging. Findings include the following:
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- Both waste and reef, proved to be “free-digging.” No drilling and blasting was needed. Material was extracted utilizing a D9 bulldozer and 80 tonne excavator and hauled utilizing 40 tonne articulated trucks (see Figures 1 and 2 below).
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- Nearly 75,000 tonnes of waste and 30,000 tonnes of reef was moved, a ratio of 2.5- to-1. Given the large size, geometry and position of the pit within the resource area, Novo considers this a reasonable trial of potential future extraction of reef at Beatons Creek. Cost of delivering each tonne of reef to the run-of-mine (“ROM”) pad came in less than AU$10/tonne inclusive of site and road preparation, stripping, and extraction of reef.
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- The top and bottom of the reef horizon proved to be readily visually identifiable based on large boulder size and abundance of oxidized detrital (“buckshot”) pyrite (see Figures 3 and 4 below). Exploratory trenches were dug into the pit floor as waste was removed allowing for a precise determination of the top and bottom of the reef while mining.
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- The excavator operator was readily able to feel the contrast between overlying waste material and the top of the boulder-rich reef while stripping. While excavating reef, similar contrast was noted with the underlying sandstone proving
much softer than the reef. These observations are very important because it
indicates that excavator operators can use hardness as a guide for future mining.
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- Minimal (<10%) dilution was incurred.
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- The reef proved to be continuous and predictable across the entire bench.
Thickness ranged from about 0.4-2.0 meters (see Figure 5 below). In places, bowl- like depressions were encountered at the base of the reef where it would rapidly thicken.
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- Locally, the reef appeared to be comprised of two or three closely stacked sub-reefs. Interbedded sandstone partings up to 0.5 m thick sometimes occurred between such sub-reefs. A bright white sandstone marked the base of the reef making footwall determination easy (see Figure 6 below).
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- No offsetting faults were encountered removing concern that the reef might be dislocated and difficult to follow.
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- Reef appeared consistently mineralized with similar amounts of buckshot pyrite across the entire bench. Small samples were routinely collected, crushed and panned, all yielding visible gold grains. A determination of gold grades will come from data gathered during trial processing.
“We are very pleased with the results from our bulk sampling exercise,” commented Dr. Quinton Hennigh, President, CEO and director of Novo. “We were able to readily identify and selectively extract targeted gold-bearing reef material with minimal dilution. All aspects of this exercise indicate we can extract conglomerate cheaply and effectively.”