Hello everyone, I noticed all the talk about what RSH and what the oz's of Au could be, well for what it's worth, here is a basic formula to estimate tonnage as well as oz's in the ground, keep in mind this is only a rough estimate, many factors should be considered for more accuracy;
Oracle
The calculator is a very basic and gives misleading results. It is interesting and fun to use, but really shouldn’t be used. It assumes continuity and equal spacing for the drillholes, assumes a specific gravity, and gives you the contained value of gold. The total contained gold figure gives you an order of magnitude figure though.
There are many ways to estimate mineralization, however all work in a similar manner.
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Estimate the size of the zone.
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Tyhee provides maps so you can get a sense of how long and wide the zone is (its strike length, width and depth)
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It is important that the zones are continuous and that the drillholes correlate. You may get a sense of this if all of the holes within the zone return good grades at similar down the hole depths.
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You can assume most rocks have a density of 2.7 grams per cubic centimeter, so length x width x depth x 2.7 would tell you how many tonnes are in the zone.
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Estimate the grade of the zone,
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Look at the grades in each area and try a “total (metres x grade)/total metres) calculation (like the online tool calculator gives you).
For example, a 250m long, 15 m wide zone drilled to 200 m should contain around 750,000 cubic metres which should represent around 2,025,000 tonnes. At an average grade on 4 grams of gold per tonne this would contain 8,100,000 grams of gold. Because each troy ounce of gold weighs 31.1034768 gms, this works out to 260,421 troy ounces of gold. As these are estimates, we would normally round this to 260,000 troy ounces.
You could determine the value of the contained gold, but it is very difficult to mine 100% of a deposit, and next to impossible to extract 100% of the contained metal. Engineers tend to apply extraction factors (maybe 60 to 90%) and recovery factors (70 to 97%).
To estimate its value is up to the investor or registered analysts. Some value it at nothing, some to the estimated difference between what the gold is worth, and what it would cost to extract (cost of production might range from $100 to $700 per ounce).
