This ear wire is nice because it has flex to it and it closes completely like a lever back ear wire. In the pics I made a pile of various hoops which is how I often make things: in groups. You are doing the same steps anyway so why not make several and have a selection. The hydraulic press comes in handy because if you hammer these circles or put them through the rolling mill it deforms the perfect circle or leaves marks you don’t want on your metal. Pliers with one round nose and one flat nose are best because they don’t leave marks either. So, if you don’t have a pair of them get a couple in different sizes.
I have made all the same in copper and copper/sterling mixed together. It all looks great and works the same.