Not sure what the question is. The persona for a gold an copper miners would be the same as any other industry. You would have a persona for the end user, the economic buyer and the champion. (see step 12) They might or might not be the same person. My guess is that they will not be. The miner is most likely the end user but that does depend on what your high level product specification is, step 7.

Assuming you are referring to a gold mining company looking for the persona of their customers, and that the company has its own refinery to produce gold bars, then there is a huge number of possible markets to sell into, take a look at this article: https://geology.com/minerals/gold/uses-of-gold.shtml. Each one with its own DMU and persona’s.

It depends on what the mine produces. Determine what products or raw materials they will produce and then understand the supply chain for those materials. The customer will be determined by the purity of the mines production. In the vast majority of cases it will be a product similar to an “industrial material” (i.e. highly technical and specialized product with a very specific customer)  rather than a commodity. A gold and copper mine will typically produce at most two products 1) “copper concentrates” with a raw material containing payable copper and gold that is sold to a smelter and 2) “gold concentrate” which is smeltered onsite and then sold to a refinery. There are others but typically the mine will produce a highly specialized industrial material that will require additional treatment before becoming a tradeable commodity (even then there are nuances e.g geography).