These are a beautiful imitation of drusy quartz in a blue with flecks of green and are absolutely gorgeous.
They are 10 mm in size, not rounded but flat, and have black edges.
A 5 mm nickel plated neodymium magnet is attached to the piece and an 8 mm enamel painted ceramic magnetic holds it on your ear for complete comfort.
Handmade in the USA by Laura Wilson
Sold as a pair.
Need extra or stronger magnet backs? They are listed here:
If you have misplaced your metric ruler, remember that 13 mm=1/2 inch.
Remember: The wider the magnets, the more comfortable the earring is.
If you are allergic to nickel, order only earrings that have both enamel painted ceramic magnets front and back since the neodymium magnets are plated with nickel.