Dear Dilip Majumdar

In summary, if you want to determine PGE concentrations accurately, a carefully planned fire assay procedure is probably best.

Clarification

My understanding is that you are trying to determine the concentrations of different platinum group elements (PGEs) in ore samples.

Platinum Group Elements (PGE)

These elements usually occur in low concentrations in ores, which makes them difficult to analyse. For this reason selecting the correct analytical method is important and often challenging.

X-ray Diffration (XRD)

XRD can be used for phase identification and quantification. It is, however, a semi-quantitative method with low resolution. It is not well suited for identifying and quantifying PGE-containing phases. Also, it cannot provide you with concentrations of the PGEs themselves.

Scanning Electron Microscopy (SEM)

SEM by itself is not a technique for determining concentrations of elements in a sample. One requires EDS or WDS for that. There are combined techniques that are very useful, such as QEMSCAN and XBSE.

Energy Dispersive X-ray Spectroscopy

EDS is a good technique for identifying and quantifying elements, but is not fully quantitative and not accurate enough for many applications.

Wavelength-dispersive X-ray spectroscopy

WDS is accurate, slow and expensive. It is probably the best for determining concentrations, but many times not feasible.

Fire Assay

Fire assaying is still the method of choice when doing accredited PGE and precious metal assays. It may be challenging to extract all the PGEs from the sample, and this will require some thinking and careful preparation.

All the best

Johan

I Know that fire assay is the best method of determining PGE concentration but my question was not answered properly.

If that is the case, please clarify your question.