Wheel Earrings are made by carefully shaping a thin rod of glass in a 2,000 degree flame. The glass is formed into a circle using heat and gravity and then the raised dots are added around the outside. Made with Borosilicate (Pyrex) Glass, Life Time Warranty. Fish hook ear wires and jump rings are sterling silver. Approx. 1.25" Tall, 1.25" Wide Each piece comes with info card about the artist and how the piece is made.