The United States quarter dollar, a denomination of currency valued at 25 cents, once contained 90% silver. This composition was standard for circulating coinage for many years. This silver content provided intrinsic value beyond the face value of the coin itself.
The rising cost of silver, coupled with increasing demand for coinage, made maintaining the 90% silver standard economically unsustainable. Continuing to produce silver coinage at the existing rate would have placed a significant strain on the national silver reserves. The decision to change the composition was a pragmatic one driven by economic realities.