3/4” long 1/2” wide Unsure of the cabochon. Looks similar to Hubei turquoise or a type of chrysocolla, may even be a simulated material. Stamped “Sterling” on post back and post base. Extremely lightweight. Screw backs do not seize, they spin smoothly and make full contact. Secure the screws as needed for a secure wear. Shop my closet for more items…..Bundle & Save!