Identifying suspect rhodium nuggets

[Critical mass 999]

I have had these things for 15 years or so I found them and at first thought it was pieces of meteorite. They're showing all the signs of being rhodium or some other Platinum group metal I tested them with Platinum aqua regia test all of the lines never even faded. Can anybody help me with maybe identification and selling of these if my acid test is correct

 

[Lino1406]

Meteorites may include osmium and iridium too. Take to XRF exam

 

[Justincase]

Do you have a local museum?
If you think you may have a meteorite you should not harm the specimen.
Take it in, and they will tell you if you have something not of this earth.
When you say "Showing all the signs of platinum group metals" what do you mean ?
Platinum group metal on the whole only show up as a trace impurity within other ore's.
It would be extremely unlikely that you would manage to get enough P.G.M. into a solution to test without considerable preparatory work.

 

[galenrog]

The rocks shown have no visible characteristics of meteorites, so let’s toss that possibility aside. If you still believe they may be meteorites, have them evaluated by a professional who has experience identifying meteorites. The average geologist at a college or university has nearly zero experience with meteorites.

PGMs? Justincase is correct that in most circumstances, PGMs are found as trace elements in other ores. There are very few areas of the world where they are concentrated enough to be a primary or secondary mining target. Even fewer areas where PGMs can be found in nugget form. The occasional platinum nugget found in extreme SW Oregon and extreme NW California is dull silver in color. Yours are not.

We have seen many examples on this forum where an XRF identified arsenic in rocks as iridium. If the XRF was not built to analyze ore samples, or does not have arsenic in its library, that should also be discounted. If you had homogeneous metal samples, I would have a different opinion on employment of an XRF.

Now we can get to any tests you may have done. You mention an Aqua Regia test. Please tell us the details of how you performed this test, and the results. Leave out no detail, no matter how small. How was the sample obtained? How was it prepared? How were the acids employed? Was there a complete digestion of the sample? The questions go on and on, but this is really the only evidence you have given, and you have given no details. I would like very much for your tests to be both positive and definitive for PGMs.

Time for more coffee.

 

[butcher]

looks like common Iron nodules
https://sites.wustl.edu/meteoritesite/items/concretions/
https://www.sciencedirect.com/topics/earth-and-planetary-sciences/concretion
https://www.google.com/search?q=ironstone+nodules&hl=en-GB&sxsrf=ALeKk03k285NayXJbrTX-2cHYKO39NRNhA:1612111592720&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjlycnWz8buAhVUIjQIHTEDC60Q_AUoAXoECBwQAw&biw=1173&bih=809

 

[Critical mass 999]

I'm I'm thoroughly impressed thank you guys for actually reading and giving me some feedback I'm pleasantly shocked oh yeah that was 15 years ago as far as me thinking it was a meteorite I actually have real meteorites now those came from a friend of mine who inherited a place where his father who was a geologist passed away and my assumption is that they are contaminants because he was obviously harvisting , and refiningPlatinum out of the hills in our area here. Cuz there's a lot of it and he had a lot of money& left my friend a lot of money, I've always been drawn to rocks and who don't love gold? Don't get me started on meteorites I might post some pictures sometime what I was kind of figuring was being rhodium and iridium and whatnot would be a contaminant if you were selling Platinum which was worth more than 10 years ago 15 years ago and then so on as far as Aquarius test I used the standard Platinum test with the nitric and hydrochloric. I used scratch Stone. And your lunch didn't fade or or nothing I mean they just sat right there maybe even got a little brighter I think I'm not really equipped to go a whole lot further than thatyou know without access to like nitric acid and all that stuff you know i'm limited . And then you know I did that test twice and I tested the acid with the piece of chain steel to make sure the acid was still good it worked I put a small amount of the sample in a shot glass with the with enough of the test solution to come up to about the top of it and I heated it up for about 5 minutes to see if you know the color of the fluid it turned it didn't turn a bright red like they say but it turned like a dark orange

 

[Critical mass 999]

I am sorry I should be more specific. As far as the full digestion of the sample not even close. II had to put it under some heat from heat gun for about 5 minutes until warm enough to even change color. It appears that this nuggets or whatever this mineral is is very acid resistant .slightly magnetic you have to have a very powerful magnet. For it to pull hanging from the string..

 

[Lino1406]

Iridium is mostly found with lots of iron (oxides). Both are magnetic

 

[Critical mass 999]

That is true still is the question of verification, of the rhodium slag or nuggets, I still have this need to know. Lol.

 

[Justincase]

That is true still is the question of verification, of the rhodium slag or nuggets, I still have this need to know. Lol.

Have you considered sending a sample to an actual assay office to be checked?
If what you wish is a dependable answer that would be the fastest and cheapest method open to you.
I have been processing for some time and I still send out samples for MGS, AAS, and ICP.
Especially when you are learning this gives you reliable results to compare your own work to until you acquire more confidence.

 

[Martijn]

Sorry to burst your bubble. But Butcher said it earlier.
A form of iron sulfide crystal. You can find tons of those markasite spheres and cylinders on the beach at the white limestone cliffs at Calais and Dover. The so called 'opal coast', but there is no opal... :lol:
It's form of pyrite.

They are formed in the limestone along with flint stone. Used together by the ancients for fire making and used for arrow head shaping.


Break one in half. It will look like this:

From wikipedia: https://en.wikipedia.org/wiki/Marcasite

Had a couple handfull of those we collected at Calais sitting in a bucket for years in a corner of the yard. They got all rusty and i threw them away.

Martijn.

 

[butcher]

In some areas, finding these iron nodules is a good thing, as some of the same earth building processes that make these iron concretions can also be the forces that can concentrate the gold in that area, as we know gold is normally associated with iron, the only problem is they drive metal detectors crazy, iron is common most everywhere around the world concentrations of gold are not always that common.

I believe some types of these iron modules were formed from ancient swamplands or something similar, but like today where we can find fossils of ocean life in the mountains, or fossilized wood in a desert, the land of ancient times were much different and the environment today may look much different from its past, I have found different types of these modules in many different environments the desert, the plains, thickly forested lands and along beaches.

Maybe someone with some understanding of geology can tell us more about these iron rocks, I have always been fascinated by them but know almost nothing about them.

 

[Critical mass 999]

Well I don't think it would be fair me not to share what I've apparently there's a form of stainless steel cirenium. That is actually resistant to most oxidizing acid. Here's my excitement and confusion. I love learning I guess even if it's expensive being disappointed

 

[Critical mass 999]

I guess they make class rings out it..