Coin silver was once a more common alloy in the United States. It is now fairly rare and the name causes quite a bit of confusion. The technical “coin silver” alloy is .900 銀, 又は 90% 銀と 10% 銅. 名前 “coin silver” is because metalsmiths historically made items from melted down scrap coin metal. At the time the name was given, coins were made from more precious metal than today. 我が国の貨幣, そして他のほとんどの, no longer contain silver and are instead made from more inexpensive, durable base metals. Some collectible coins or coin investment instruments have higher silver content. They are marked as such with a quality stamp and usually come with certificates of authenticity. 現在でも市場に出回っているコインシルバーのジュエリーには、 .900. Many of these pieces are antiques.