• To participate in the 911Metallurgist Forums, be sure to be Logged-IN
  • Use Add New Topic to ask a New Question/Discussion about Mineralogy or Microscopy .
  • OR Select a Topic that Interests you.
  • Use Add Reply = to Reply/Participate in a Topic/Discussion (most frequent).
    Using Add Reply allows you to Attach Images or PDF files and provide a more complete input.
  • Use Add Comment = to comment on someone else’s Reply in an already active Topic/Discussion.

XRF for Platinum (4 replies)

John Koenig
11 months ago
John Koenig 11 months ago

I need an Analysis for platinum in rock samples and hoping an XRF can shot platinum. Does anyone know if there is any portable or handheld analytical equipment that can quantitatively analyze Platinum in rock samples at less than 1ppm? I do not know about the current cut off limits but it would also depend on how it was picked up in your specific matrix as well.

Victor Bergman
11 months ago
Victor Bergman 11 months ago

The problem is not the pXRF device, good quality pXRFs can detect Pd and Pt at least.

For PGEs there are two big limitations, however:

  • the very low concentrations - in most samples you will get below Detectable Limits
  • even more important, PGEs are very prone to nugget effects. Handhelds analyse typically less than 1cm2 of sample, on a depth of less than 1mm. You may easily miss PGE grains. You may also over-evaluate concentrations if you hit a large grain.

I would suggest pXRF for PGE prospection as a detection tool - not quantitative - for PGE elements. But pXRF can analyse quantitatively many companion elements, such as Ni or Cr. This is more efficient than direct Platinum Element Group PGE measurement. 

Maya Rothman
11 months ago
Maya Rothman 11 months ago

Has anyone tried using a portable XRF to look for PGM's in celestite (strontium sulfate) or to look for au in sands that are over 30% Mn?

11 months ago
JohnnyD 11 months ago

I have looked for PGE's in ultramafic rocks of Bushveld (South Africa). The concentration was below 10 ppm (g/ton) so I had to define pathfinder elements (Ni and Cu in this case) and use them in portable XRF. So high concentration of Ni and Cu would suggest presence of PGEs. Also I have used XRF to find source of gold in stream sediments in Columbia. Again gold concentration was below portable XRF detection limit. But with panning, the amount of gold was increased to >15 ppm so portable XRF could detect gold.

Bill Fraser
11 months ago
Bill Fraser 11 months ago

With PGEs and with Au, detection limit is not the most important feature. In many cases, their distribution is highly heterogeneous, with frequent nugget effects. In this case, the pXRF beam may miss its target and give false negatives. This can be addressed only by multi-shooting and may be impractical. Remember that PGE and Au analysis often need larger samples for lab analysis. On the opposite, a confirmed positive obtained by pXRF is an effective detection (above 3 sigma) of the precious metal, but the value itself has little meaning.