Copper

Copper has a beautiful interaction with glass.  It is one of the few metals that tends to be compatible with glass casting — most other metals, unless very thin, will cause the glass to break.

The following experiments used copper Monster Cable speaker wire.  These are just experiments, so I left them in their raw state, cutting the edges to be square, but without polishing.  The glass is Uroboros COE 90 (Bullseye compatible).