A bag of 90% silver U.S. coins is a collection of United States coins minted before 1965 and containing 90% silver. These coins were widely circulated in the United States until the mid-1960s when the U.S. Mint switched to copper and nickel in their coin production.

These bags of  90% silver U.S. coins consist of dimes and quarters minted from 1916 through 1964. Each of these coins contains varying amounts of silver depending on its denomination. A dime, for example, contains 0.07234 troy ounces of silver, while a quarter contains 0.18084 troy ounces of silver. With a total face value of $1,000, each bag contains approximately 715 ounces of silver. 

Today, such bags are often used as a form of investment for those who want to hold physical silver or diversify their investment portfolio. These 90% silver coins are widely recognized and are an appealing option for those looking for smaller, easily negotiable increments of silver.