The United States Mint notified its authorized purchasers June 23 that the bureau was temporarily sold out of the 2014 Shenandoah National Park 5-ounce silver quarter dollars.

The memo added, "We will be striking additional coins and will notify you when they are available for sale."

The bullion version of the 3-inch .999 fine silver coins are struck without Mint mark at the Philadelphia Mint. They are not sold directly to the public, but through a network of authorized purchasers who buy the coins based on the spot price per troy ounce on the London PM fix, plus a $9.75 premium per coin.

The Philadelphia Mint also strikes a numismatic version, with P Mint mark, that the U.S. Mint does sell directly to the public.