What can you do with a central heating's copper pipe?

We changed our boiler last August and I kept all the good pieces of pipe that the plumber discarded.

I made these two items with one piece of pipe, hammered flat, sawed into shape and then soldered to create a big and bold jewellery set... 

Extra materials include scrapped silver and a rough emerald I was sent with a junk mail letter - my teacher told me they are real but not precious as flawed and uncut.