CMC Mint came to my attention when I was researching the provenance of some silver rounds I bought from an intermediary in 2003.
The rounds in question were a bit on the light side for one troy ounce and I was concerned that they were fake, but a drill assay and x-ray analysis at the London Assay Office confirmed that they were .999 silver. From the design, I was confident that they were from the CMC Mint.
Anyway, I looked on their website and it's quite interesting. It's not somewhere I'd choose to buy silver from, and you should be extremely careful about the definitions used, eg German silver is not silver at all, and mils silver .999 is NOT .999 fine silver.
The reason I'm posting it is that they sell bars and rounds of a number of exotic metals:
If you are thinking of buying from them, I'd say order a relatively small amount first so that you can check the mint quality and weight before you commit a higher sum.