FUJIYAMA is made using traditional casting technique which has been handed down in Takaoka for generations. Because tin has been known to absorb impurities and purify water, and that tin removes excessive bitterness from sake, tin cups have been used to enjoy sake from old days in Japan. It is common to add other metallic materials to provide durability and facilitate cutting work, but NOUSAKU uses tin without such additives to maximize setallic property. We hope you enjoy a special moment, along with Fujiyama inside the cup. [Care & Maintenance] Wash with mild detergent using soft cloth (sponge). Polish with commercial metal cleaner, toothpaste, or baking soda to bring out the luster. [Cautions] Do not put the product over a fire nor use it in microwave ovens.The melting point is low. Use of scrub brush is also prohibited.