Help Identify PGM ore
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kurtak
Well-known member
suf190 said:
The only way to tell FOR SURE - is to have an "actual" assay done on "the rocks"
other wise - they are just rocks
Kurt
There is a set of chemical tests on the forum that can be used to test ores. They will confirm what metals are present but not the quantities.
Cheers Wal
Cheers Wal
galenrog said:
This is exactly what needs done.
There's been a recent onslaught with high PGM prices of everyone and their mother thinking they have valuable rocks.
Why lease a mine without knowing what is even in it?
Hard to tell from the pictures, but it looks like galena, sphalerite or pyrrhotite mainly with other sulfides present. In other words, a complex sulfide ore.
Be aware that most XRF-guns mistakenly identifies arsenic as iridium if there isn't a library for mining included in the machine. Arsenic is commonly found in sulfide ores in the form of arsenopyrite. Treating this type of ore chemically or with heat can convert arsenic into compounds that goes up into the air and can be inhaled. We have several members that have hurt themselves that way. Just look at Irons, hospitalized for months from acute arsenic poisoning when roasting ore.
Collect some samples and send it in for analysis.
Göran
Be aware that most XRF-guns mistakenly identifies arsenic as iridium if there isn't a library for mining included in the machine. Arsenic is commonly found in sulfide ores in the form of arsenopyrite. Treating this type of ore chemically or with heat can convert arsenic into compounds that goes up into the air and can be inhaled. We have several members that have hurt themselves that way. Just look at Irons, hospitalized for months from acute arsenic poisoning when roasting ore.
Collect some samples and send it in for analysis.
Göran
Rick & Carrie
Prospectors Rick & Carrie of Geotech Analytical
Photo #2 contains sphalerite, so gold and silver are quite likely in ore of that variety and grade.
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As stated above - send it to lab. The tests in "Duke's" (available on this site) is a good way to determine what elements are present. You can then assay for just those metals. You also need to know what the mineral is to determine recovery methods.
Update : After wasting a lot of money on fire Assay tests with ICP, we managed to get in touch with a refiner who did a sample refining of 20kg and a gravimetric test we got the result in the attached pic. Looks like we were not wrong. Lesson learned, fire Assay does not work well for PGMs.
I'm no rock hound, but these numbers seem strange.
What did he do to the ore and how did he test it.
If PGMs are suspected, I believe that Nickel Sulfide fusion and cupellation is needed to get correct numbers.
Relatively nice numbers. Actually very nice. Does the ore comes from Poland ? As I see polish text in the pic
because it is not common to encounter PGMs in Central Europe.How the bulk sample processing ended ? Which process did they used ? Classic crushing followed by tabling of concentrates or sluicing ? This is very important to know, as some sulfides with finer grain can be lost in the process. Simple analysis of cons should also be done, not to toss away precious metals in the gangue.
Fire assay on PGMs is hard, and not very much fire assay offices (and here in C.Europe practically never existing for one-time public customers - as mining here ceased to near zero...) does it well. Completely different process from gold assaying.
I learned that in bulk (around 100g of sulfide cons for example), one can perform something similar than fire assay - with +-5-7% error margin. You would need gas or electric furnance, induction furnance is best in my opinion, as you can heat things very reliably in it. And of course XRF machine - needn´t to be owned, just for measuring resulting button. Some cupels which could hold 100g metal, and then oxy/propane burner - or that induction furnance. And bismuth metal.
1. obtain the concentrate of heavies/sulfides and roast it properly.
2. add the bismuth collector metal and flux. If your ore is high in Pb, you want to add at least two or better three times more bismuth than is the lead content of the sample. this is because PGMs are much much better soluble in Bi than in lead. Including Rh.
3. Smelt the whole lot down, obtain BiPb dore, inspect the slag for homogenity and possible inclusions of metal beads.
4. Cupel away PbBi to maximum extent. If you will have PGMs, and espetially Pt or Rh in the sample in significant quantity, bead freezes quite quickly. Nevermind
5. heat the bead with oxy/propane or in induction furnance if the bead is big enough to be "catched" by induction, melt it and cool it down in reducing flame.
6. if significant ammount of PGMs were present, you obtain button which could be crushed with hammer and crumbles analyzed with XRF. Note that PGM alloys with Pb or Bi are brittle and cannot be flattened as regular AuAgCu alloys.
You know the starting weight of the sample, so in the end you can easily calculate the PGM content of the ore based on PGM content in the bead measured by XRF. This "methodology" has it´s own error margin. But costs few euros if performed in your shop. And can be done reliably with less than 5% error, if one practice it for some time
The Ore is from K2, extremely inaccessible mine. It has been very difficult to find a partner to refine this material for us. Separation of Rh seems very difficult for most refiners.Relatively nice numbers. Actually very nice. Does the ore comes from Poland ? As I see polish text in the pic
How the bulk sample processing ended ? Which process did they used ? Classic crushing followed by tabling of concentrates or sluicing ? This is very important to know, as some sulfides with finer grain can be lost in the process. Simple analysis of cons should also be done, not to toss away precious metals in the gangue.
Fire assay on PGMs is hard, and not very much fire assay offices (and here in C.Europe practically never existing for one-time public customers - as mining here ceased to near zero...) does it well. Completely different process from gold assaying.
I learned that in bulk (around 100g of sulfide cons for example), one can perform something similar than fire assay - with +-5-7% error margin. You would need gas or electric furnance, induction furnance is best in my opinion, as you can heat things very reliably in it. And of course XRF machine - needn´t to be owned, just for measuring resulting button. Some cupels which could hold 100g metal, and then oxy/propane burner - or that induction furnance. And bismuth metal.
1. obtain the concentrate of heavies/sulfides and roast it properly.
2. add the bismuth collector metal and flux. If your ore is high in Pb, you want to add at least two or better three times more bismuth than is the lead content of the sample. this is because PGMs are much much better soluble in Bi than in lead. Including Rh.
3. Smelt the whole lot down, obtain BiPb dore, inspect the slag for homogenity and possible inclusions of metal beads.
4. Cupel away PbBi to maximum extent. If you will have PGMs, and espetially Pt or Rh in the sample in significant quantity, bead freezes quite quickly. Nevermind
5. heat the bead with oxy/propane or in induction furnance if the bead is big enough to be "catched" by induction, melt it and cool it down in reducing flame.
6. if significant ammount of PGMs were present, you obtain button which could be crushed with hammer and crumbles analyzed with XRF. Note that PGM alloys with Pb or Bi are brittle and cannot be flattened as regular AuAgCu alloys.
You know the starting weight of the sample, so in the end you can easily calculate the PGM content of the ore based on PGM content in the bead measured by XRF. This "methodology" has it´s own error margin. But costs few euros if performed in your shop. And can be done reliably with less than 5% error, if one practice it for some time
This was why I asked him how it was processed.Relatively nice numbers. Actually very nice. Does the ore comes from Poland ? As I see polish text in the pic
How the bulk sample processing ended ? Which process did they used ? Classic crushing followed by tabling of concentrates or sluicing ? This is very important to know, as some sulfides with finer grain can be lost in the process. Simple analysis of cons should also be done, not to toss away precious metals in the gangue.
Fire assay on PGMs is hard, and not very much fire assay offices (and here in C.Europe practically never existing for one-time public customers - as mining here ceased to near zero...) does it well. Completely different process from gold assaying.
I learned that in bulk (around 100g of sulfide cons for example), one can perform something similar than fire assay - with +-5-7% error margin. You would need gas or electric furnance, induction furnance is best in my opinion, as you can heat things very reliably in it. And of course XRF machine - needn´t to be owned, just for measuring resulting button. Some cupels which could hold 100g metal, and then oxy/propane burner - or that induction furnance. And bismuth metal.
1. obtain the concentrate of heavies/sulfides and roast it properly.
2. add the bismuth collector metal and flux. If your ore is high in Pb, you want to add at least two or better three times more bismuth than is the lead content of the sample. this is because PGMs are much much better soluble in Bi than in lead. Including Rh.
3. Smelt the whole lot down, obtain BiPb dore, inspect the slag for homogenity and possible inclusions of metal beads.
4. Cupel away PbBi to maximum extent. If you will have PGMs, and espetially Pt or Rh in the sample in significant quantity, bead freezes quite quickly. Nevermind
5. heat the bead with oxy/propane or in induction furnance if the bead is big enough to be "catched" by induction, melt it and cool it down in reducing flame.
6. if significant ammount of PGMs were present, you obtain button which could be crushed with hammer and crumbles analyzed with XRF. Note that PGM alloys with Pb or Bi are brittle and cannot be flattened as regular AuAgCu alloys.
You know the starting weight of the sample, so in the end you can easily calculate the PGM content of the ore based on PGM content in the bead measured by XRF. This "methodology" has it´s own error margin. But costs few euros if performed in your shop. And can be done reliably with less than 5% error, if one practice it for some time
The numbers on the phone almost seem …. well, made up/extraordinary.
And the Polish text don’t correspond with what I expected from the rest of the post.
So Suf, please respond to the questions asked.
K2 the mountain in the Himalayas?
Or are there other K2 around?
It is a rare material, for refineries, AuAg are their bread and butter, PGMs can behave strange, they are much likely to not be extracted 100%, stubborn BM such as nickel, cobalt and iron are in the ores, making difficulties with hydrometallurgy and pyrometallurgy...
Aside of this, recovery of PGMs by pyrometallurgy from sulfide concentrates isn´t that problematic. What is problematic is their resolution and rafination
But firstly, pyrometallurgical cons reclaiming is very money-intensive, so the ore should have appropriate grade for this to be done. As with PGMs, leaching options such as cyanide for Au are hardly existing.
K2 ? Very unecpected, in combination with Polish assayers office. I would like to hear that story how you came across the mine on K2...
Yes ...... K2 part of the Himalayan range
Bulk processing is yet to be completed. 23 Tonnes of the material is currently en route to the refinery. We initially had the materials tested by a lab in Germany (results attached). 4 samples from 4 separate veins were sent for analysis. As per the suggestions on the forum, when we did a full analysis using Fire Assay from SGS in Canada, the results showed nothing. However when sample from the same vein was sent to Germany and Poland, who as far as I know, did gravimetric tests we got the results as was expected
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