11x18mm or 7/16" x 11/16" diameter. great size to use for Raven Cosplay as a forehead diamond! They are lead free (safe for skin!). I used eyelash glue to attach to my forehead. Good for creations at scrapbook and craft works, Perfect for card making, scrapbooks and body art. Add your own glue. Used for cards and invitations, jewelry, face painting, costume making, cosplay embellishments.