Yes, we, as well as the other assay offices do a "melt and assay" service, which of course is different from refining. Basically we would melt the crucible into a bar, and then we would assay the bar. (With refining, you extract all the non precious metal and you're left with a bar of fine gold - far more expensive and then of course you'd have the extra headache of alloying the gold down into whatever carat you wish to use!). You'll get a certificate with the bar giving you details of the gold content, and the certificate will have a unique number, which is also stamped on the bar. Bullion doesn't get hallmarked as such as it's exempt from hallmarking, but the cert number stamped on it, which corresponds to the certificate, is what you get instead. You then have the option of "selling on certificate" which means that you don't have to lug the bar around with you, just the certificate, and bullion dealers will buy from the details on the cert. Once you've got the best price, then you can arrange to hand over the bar.
Just check with whichever assay office you use regarding turnaround times - it's not like hallmarking where you can do the job in an hour if you're in a hurry - most melt and assay work takes several days.
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