Only tried on once. Alcohol-sterilized. Price includes the case. From the online jewelry shop where I purchased it: The stones we use are Jeulia® Stone (Jeulia® stones), the best alternative to natural gemstones. They have almost the same brilliance as diamonds and also have excellent hardness. Unlike natural gemstones, which are mined from the earth through dangerous operations such as large machinery and explosives, Jeulia® Stone has developed highly durable stones with superior optical properties to diamonds, based on the philosophy of environmental protection. Men's Women's Jewelry Earrings Accessories