United States quarters minted in 1964 and earlier contain 90% silver. These coins are often sought after due to their precious metal content, distinguishing them from later issues composed primarily of copper and nickel. For instance, a quarter dated 1964 would possess this silver composition, while one from 1965 would not.
The significance of these earlier quarters lies in their intrinsic metal value, which fluctuates with silver prices. This makes them attractive to collectors and investors alike. The historical context is important because the switch to base metal coinage reflected rising silver prices and the need to conserve the precious metal for other uses. This shift marks a clear demarcation in US coinage history.