Hello, floridaunderground.
Retail jewelry has a very high mark-up. As a result, selling jewelry to a retail store will not bring near the original price, if a retailer is even interested ...
Mixed gold & copper (22, 18, 14, 10Kt, etc...) will not bring it's gold melt value, as refining costs time & money, & the buyer will want to make a profit above that.
As far as stones, such as diamonds, rubies, etc. ...the mark-up on those are way more than mark-up on metals. These stones are plentiful, & have little to no value to a jewelry store ...
...You may find a jeweler who will take the items on consignment, but, expect to pay anywhere from 25% - 45% commission.
...I would look for someone local, a small operator, who makes custom jewelry, & sell the items to them ...
Or, to sell the pieces, you may consider, venues such as Etsy, eBay, Craigslist, etc. In my experience, these venues will bring the best returns on your jewelry.
Oh, and pawn shops?....fagiddaboudit ...