I made those earrings with beer cap and recycled copper.

Step 1: WHAT YOU NEED

MATERIALS:
-2 beer cap (choose some with a nice inside color, some are bronze looking, choose those, not the iron looking);
-copper wire (you can take it out an electric wire);
-2 earring hooks.

TOOLS
-claw;
-screwdriver (flat one and star one);
-hammer;
-knives;
-piece of flat wood;
-dremel (not on photo).

Step 2: FLATTEN CAP

with the hammer flatten the cap on the piece of flat wood, before flatten the edges and after the middle, one side and after the other.
(don't do it too fast or the cap will brake open)

Step 3: REMOVE PLASTIC FROM CAP

with a knives remove the plastic from the inside of the cap, then flatten again on an hard surface.

Step 4: MAKE HOLES

with the star screwdriver and the hammer make some holes in the cap, colored face up.
then do smaller hole (beat less with the hammer) all around the edges (so they will get bend a little)

Step 5: BEND EDGES

to bend the edges a little bit more use the flat screwdriver: beat it with the hammer all around the edges of the cap.

Step 6: CLEAN THE BACK

with the dremel clean the color of the cap away, or varnish it.

Step 7: SMOOTH EDGES

with the dremel smooth all the edges, also the ones of the holes

Step 8: DECORATE

decorate the caps with the wire, insert it from one hole to the other (thread it 2 or 3 times), close it in the behind of the cap, and flatten it (it wont touch your face cause the cap is convex)