Is copper really worthless?

I bought this 1 ounce Copper coin and it doesn't even have a face value even a penny has a face value of 1 cent,If you look at a copper penny in a bowl compared to most other coins/metals it looks so pathetic, corroded as if it going to disintegrate away, there are some metals that you can weld and the fusion process works well, but if one tries to weld on copper it basically blows up. Yes I know it is supposedly useful for plumbing but even there Im skeptical about health because of the intense corrosion that takes place when its combines with water and other liquids.Just wondering if anyone knows any true value for this metal or is it as worthless as I think it is?? Thanks in advance =]