Trading
Assay settlement, and what an umpire actually does
Assay settlement sounds adversarial and is the opposite: it is the mechanism that lets two parties who do not trust each other trade anyway.
How a lot is priced
Once a lot has been decanned, homogenised, sampled and assayed, its value is arithmetic:
- Assayed grammes per tonne of platinum, palladium and rhodium, multiplied by the lot weight, gives the contained metal.
- Contained metal, multiplied by the metal prices agreed for the lot, gives gross metal value.
- Less treatment and refining charges — what the refinery charges to actually separate the metals — gives payable value.
Every one of those three lines is negotiable before the lot moves, and none of them should be a surprise afterwards. Ask us to walk through the arithmetic on a real lot of yours and we will, line by line, before anything is collected.
Where disagreements come from
Not from the arithmetic. They come from step one: whether the sample that was assayed genuinely represents the lot. A lot that was not properly homogenised before sampling can assay high or low by a margin that dwarfs anything being argued about elsewhere in the schedule.
This is why the decanning and milling step is worth being slow about, and why a supplier is entitled to ask how it was done.
What an umpire is
An umpire is an independent laboratory, agreed by both sides, that assays a retained portion of the same sample. Its result settles the lot. That is the whole mechanism, and it works because it removes the incentive to be optimistic: neither party has anything to gain from an assay that will not survive an independent check.
We also engage independent laboratories where a lot needs critical-minerals analysis rather than a routine PGM assay — some material is worth understanding in more detail than a settlement strictly requires.
What to ask a buyer
- How is the lot homogenised before sampling, and who witnesses it?
- Is a portion of the sample retained, and for how long?
- Which laboratory acts as umpire, and who chooses it?
- What are the treatment and refining charges, in writing, before the lot moves?
A buyer who cannot answer those four is not offering assay settlement. They are offering a guess with an assay attached to it.
