Copper tubing is easily available from the hardware store.  It's what plumbers use. Different sizes of copper pipes can be used in jewelry making.  Some sort of cutting tool will be needed such as a pipe or tube cutter or hacksaw.

Sysiphus created this tutorial on how to make a ring from copper pipe (see picture above).  What diameter copper piping will depend on the size required.  Shown above is a size 9 - 9.5 made from  3/4" piping. It's easier to stamp on flat metal but it's not impossible to do so on the copper ring if one has a mandrel to hammer it on.

 Other easy thing to make from copper pipes are simple beads as all you have to do is cut small sections of tubing.  Lynda Carson's Smashed Copper Tube Bead tutorial over at Making Jewelry Now shows one way to do so. (Update: picture only, link no longer available).

Image by Lynda Carson
A super way to add a design is to stamp the copper beads!  Check out this tutorial for the tips and tricks. Alas there are no pictures. It makes sense to feed the shaft of a screwdriver through a copper bead, secure it so it doesn't move and then stamp. GeltDesigns has a series of copper pipe jewelry tutorials on the New Jewelry A Day blog.  The earrings tutorial uses simple copper beads. These could also be connectors in larger jewelry projects.
Image from New Jewelry a Day
A more involved project is the Bangle Bracelet from Copper Pipe tutorial also from New Jewelry a Day. The lovely blue patina was achieved with ammonia.
Image from New Jewelry a Day
If you're not into sawing or cutting pipes, check out the copper couplings from the hardware store. Erica from P.S. I Made This did and came up with her chunky Rose Gold Necklace tutorial.  The use of a bent coupling is inspired! (Update : link no longer works)

Prefer smaller pipes?  Then check out I SPY DIY's Nautical necklace and her modeled pictures.  I just love the coordinating leather cords used to hold the copper tubing in place.  Her clasp is a carabiner!
Lynda Carson of Fresh Baked Designs shared her experimental copper tubing bangle on Rena's Making Jewelry Now blog. (Update : link no longer available)

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