The disc is oxidised silver 13mm diameter and covers the whole lobe. The backs are silicon and displace weight so you will find them very comfortable. Labradarite is my all time favourite stone originating from the top of Canada in the province of Labrador, the stone is greyish and opaque with shots of blue green iredecence. Total drop of the earring is 38mm. Edition of three only and is available from my on line shop. $250.