Quality vajazzling crystals can and should be re-used. This depends in part on the backing of the crystal. If it is a Swarovski flatback, then the crystal can be used over and over again with skin safe adhesive. For optimum shine, polish the crystals with a soft lint free cloth before reusing them. Treat them like you would any other quality stones by making sure not to get them scratched up. And remember to store them properly.