You are correct in regards to even the most technologically advanced processor has to use the law of average, but you're wrong to assume people don't know which catalysts contain platinum and which contain palladium.
In fact you're very mistaken in this subject as we have a catalogue that details exactly which catalysts are platinum and which are palladium. Over 90% of the time you don't even need to test to know, as Diesel motors run platinum and Petrol palladium most of the time.
The law of average thing is correct because unless you are shipping tonnage of ceramics out to the furnace, they have to do a simple mill / xrf of each batch, before bulking it up with other batches before it finally hits the furnace.
Edit: You don't have to spend a lot of time with a hit and miss campaign as stated above either. We are more than happy to offer our catalogue to everyone. This will give you a reasonably accurate protrayal of returns before refining. IF you want to sell for catalogue price that's fine but if you want toll refining your returns will be even higher than that displayed on our catalogue.
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