Fire Assays and how to read them

Something that has come up recently in conversations I have had with Miners: How to read your Fire Assay results. Many miners want to know what values are in their materials… particularly as it relates to their black sands.

There are thousands of YouTube videos of how to get gold out of black sands. Some are good… some are not. Virtually all black sands do contain some value of gold, platinum, palladium… something. The trick is to know if it is worth the time and effort to go after it. You find out by sending you black sand samples to a lab and having them fire tested. You receive a report from the lab that identifies the values in Parts Per Million (PPM).

The problem is that many do not know how to take the information and make use of it. So a quick example:

The testing shows a Gold value of 11.0 PPM. A simple way of converting that information to “what percentage of my black sands is gold” is to move the decimal point to the left 4 times… so 11.0 becomes .0011%. That is the percentage of the material that is gold.

There is no economically viable way of extracting that small amount of gold… no matter what process is used.

Viability starts at 0.1% of value… so your testing needs to show 1000 PPM or better. Less than that, better to just use it as reclamation fill.

So, 1000 PPM = 1/10 of 1%

5000 PPM = ½ of 1%

10,000 PPM = 1% of the material

Next blog.. Sluices and Fine Gold!

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