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Ask The Experts - Incorrect assays cause problems

Q: Together with some partners, I have invested in some mines in Alaska that assayed rich in both platinum metals (especially iridium) and gold. My partners and I tried with all our abilities, but no one could seem to help us extract the metals that were shown in the assays. Can you help me find a way to extract the platinum and gold?

A: I believe the reason you are having difficulty getting the values out of your ore is due to the fact that those values are not actually there. No matter how much experience some engineer or geologist has, no one can extract and recover things which are not there to begin with. There are fraudulent guys who do “special” assays; examples of these folks have been around for more than 100 years. They claim to find values that no other assay lab can recover. Since you told me that one guy out of Colorado has done all your assays, I am sort of suspecting that he is the source of your problem. 

You may wonder how I could be so sure that this is the cause. The thing is that the chemistry of gold and the chemistry of platinum group metals like iridium are very different. That’s why it is extremely unusual to find them together; the conditions which create platinum ore won’t make gold ore. The conditions that create gold ore won’t produce platinum metals like iridium, so you essentially never get them together. Sometimes there are placers with both, but in those cases the gold and platinum group metals come from different hard rock sources. A few hard rock sources, like certain copper-nickel magmatic deposits, may have traces of both platinum and gold, but only tiny traces. Having enough of both to work a small mine is something that almost never happens. Usually the dishonest assayers don’t know enough about geology to know this. That’s why when folks tell me that they have a good amount of both gold and platinum group metals in their ore, I can pretty well be sure that something is wrong, because what they are really saying is they have something that virtually can’t exist. I’ve actually seen dozens of examples of this over the years and in 100% of the examples I’ve seen the assayed values were not real.

I would strongly urge you to have samples of your ore sent to other assayers, ones that are well known in the mining industry and considered as industry standard. I expect that if you do that the respected labs will give you a much different picture of your ore and you will not have any platinum group metals beyond tiny traces that are so small that it would cost more to recover than their value. 

Another normal thing is that respected labs will charge in the ball park of around $50 per sample where the “special” labs are much more expensive, in the range of $100 to $200 and more. Some other assays by respected labs will tell you what you need to know, and I believe it’s critical that you get that done. I am sorry if you’ve invested a lot of money in this, but all I can tell you is that I think there is a big problem and that your ore may not be what you think it is.

© ICMJ's Prospecting and Mining Journal, CMJ Inc.
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