I have been using this for several months after purchase. It has been disinfected with alcohol. This is jewelry using natural onyx, the birthstone for August. Material: Brass Gemstone Type: Onyx It is metal allergy-free and nickel-free. Gem Stone King was founded in Belgium in 1903 and is now a world-leading jewelry brand with a history of over 115 years, headquartered in New York. Purchase price: 6,282 yen Please use the price reduction request for price negotiations. Also, if you wish to purchase with other products, a small discount is possible. Please feel free to ask any questions.