funnyNo.
You send me a bar.
Personally I would prefer the shiftiest one you have as it gives me some work to do.
I do prefer to work on an actual recovery.
But if pushed I will work on an assay by one of the assays offices.
https://www.assayoffice.co.uk/They hermoginise the bar and then take a drop sample verified as an independent governmental sanctioned witness.