I've never had allergies to any jewelry that I've worn, so I can say that I've been blessed that I can afford cheap jewelry, I guess. However, I have ran into several people who are allergic to certain metals, specifically nickel. As a result, these folks are forced to buy expensive precious metal jewelry, poor things. But, really, who would want anything less?
So, while researching copper to see if there are any reports of allergic reactions, I came upon a very informative site: Chard's Allergies to Jewelry. The name is weird, I must say, but the site is incredibly information-rich.
My copper allergy question? Answered. Apparently, sometimes copper and silver can react with atmospheric pollutants to cause irritation, but the copper and silver themselves are not the problem.
Well, now I can continue working on the copper/glass and copper earwire creations.