What is the procedure for picking where to sample?
We have an enormous amount of historical sampling data, however it needs to be put into the proper perspective from the paper plans to the actual physical location from where it originally came from. We have the original complete surveys, we have oriented it to this to our own survey of the underground. All we have to do then is to is establish the physical locations inside the workings to the plan and we have the location of the original drill samples, and the mined round samples.
Then we have done channel sampling along the surface of the mined area to see if it coincides. Better than a drill hole as we have a greater surface area and depth of the samples. We mark it on the map, cross reference, and we have then replicated, as closely as possible, between the areas of high grade and low grade. We then mark and mine the higher grade.
You report a variety of grades from fairly low to bonanza: will your ore sorter be able to upgrade the lower grade material?
We call it upgrading, but in effect, the ore-sorter actually selects the mineralized material from the mixture of mineralized and non-mineralized material.
Most systems take all the mined rocks, crush it to beach sand size, and then float it. That is very wasteful, both energy for crushing and cost wise for the size of the flotation plant. We are preselecting our rocks, so we only have to do final concentration on 10% – 15% of the gross mined material. That savings can go straight to the bottom line as our flotation plant will be very small. Probably 20 – 30 ton/day.
As an example, the following photo shows a mineralized rock that has been broken so it can be crushed to the optimum size that will able to be sorted. The mineralization shown, is comparable to bonanza grades we have already tested, and the ore-sorter will probably select every piece of the rocks shown, as it is very heavily mineralized. Rocks that are sized smaller the 8 mm bottom limit of the sorter will be selected by the dense media system, so we will capture pretty much all of it.
The next picture shows a rock that has both mineralized and non-mineralized material in it. This rock, when crushed, is a good example of where the ore-sorter excels, selecting the mineralized and leaving the waste. Generally, anything with the darker streaks in it will be highly selective, while the brownish colored rock will be left.
The majority of the mineralization is in the hard grey rock, Rhyolite. It fractures readily when crushed and the testing we have done shows that grades even as low as 1oz – 2oz per ton can be upgraded 15 to 25 times, and we will get to select a lot of mineralized material that would be normally be left behind as not recoverable.
For example, when Silver King mined in 1984, they did not mine anything under 6 oz/t silver. Bayhorse is operating at the cutting edge of the technology that is available to recover as much as possible, even down to 1 oz/t to 2 oz/t. Of course, we will probably stay above 2 oz/t for practical reasons, but the ore-sorter is very selective with the type of rock we have.
You are anticipating a 43-101 Resource estimate shortly. Will these samples be in time to be included?
Yes. We have sampled extensively already, as well as done comprehensive testing through the sorter, and all the information, assays, etc, has been provided to Apex Geoscience for reference and inclusion in the report.
You have historic data from the 1984 mining program. How well do the reported channel samples conform to the historic data?
What the sampling has shown us is that it correlates very closely to what has been mined, and there is an enormous amount of rock that wasn’t touched in the old haulage way itself that is readily mineable with very little expenditure. We win both ways here. After all, we have around 1,000 to 1,500 feet of accessibility to the mineralization that we do not have to drift to get to. That is a substantial savings right there.
Underground mining is highly technical. What do you take and what you leave behind. Almost like building a huge medieval cathedral. You have to support the roof and the walls so it does not fall down around you. In fact, Roman architecture was so good much of it is standing after 2,000 years through their use of arches and pillars, and that is the basis, even today, of modern mines. The miners are highly experienced in doing this, so much so they can tell in an old mine whether it is safe or not just by looking at the rock pillars and seeing how much stress it is taking.
Mineralization is found, Mines are made. The silver prices are so low right now that many investors are totally disheartened and our share price has suffered, along with many other companies prices, because of it.
But money makes and operates mines, and so to make a mine and make money you need development funds, and those is hard to come by these days, so we try and watch every dollar, because making a mine is an expensive proposition.