Lovely locks

Humans have been locking up their precious things since time immemorial; the first lock was probably a stone placed in front of a niche in a cave. These days, many things are secured by electronic locks with PINs or remote controls.

You can't go past a good, old-fashioned mechanical lock for strength and beauty, though. Here are a few examples I found online: just gorgeous!  (Click on the pictures to go to the source.)