I got these floating lockets from Doreenbeads.com!
If you need a floating locket, there are some similar ones here:
Glass Circle Magnetic Floating Charm Locket with Snake Chain or
Glass Circle Rhinestone Floating Charm Locket Pendant with Snake Chain
Like the shrinky dinks from the olden days.
Grafix 8-1/2-Inch by 11-Inch Shrink Film, Printable, White 6-Pack
Okay, now all you have to do is right click to save off this printable image.
Place them ink side up on the baking tray...
They will start to curl up, shrink and lay back down.
Then they are done.
And a fun way to make a custom statement!
and rock your Whovian geekery all over town!