You got four copper tags for a buck. I bought a mess of them. No, you can't have them.
I have also used
small terracotta pots (written on with ceramic marker)
Shells (also written on)
Pot shards
Egg shells (blown, whole)
Bits of slate off of local roofs.

I have old window blinds that I use. Want these ??

Cut up aluminum soda cans.

Thanks for all the ideas gang!

Xtal

I have copper wired hang tags. Interested in a plant trade?