This is a style of bracelet made using memory wire. The wire is incredibly strong, and thus returns to it's set shape after being pulled open or moved. Size doesn't really matter, as it sits on your wrist at whatever expansion suits it.
This one is made using a gemstone known as opalite. This gemstone is frequently falsely sold as moonstone, given that it has similar colour and iridescence.
The end beads are small clapperless bells, and the spacer beads are class seed beads.
This is how memory wire bracelets are worn - http://store.tidbitstrinkets.com/bl.....eletkitarm.jpg