In 1986, the United States began striking gold bullion coins with a face value of $25 and a net weight of 1/2 ounce of pure gold.  The value of these coins is intended to be tied directly to their metal value, although some low-mintage years and all of the Proof versions fetch premium prices.

From 1986-1991, Roman numerals represent the date; from 1992 on, Arabic numerals are used.  Proof versions did not appear until 1988.  From 1988-1993, responsibility for producing Proofs fell to the Philadelphia Mint; beginning in 1994, Proof production moved to West Point.  Proof versions bear mintmarks; Uncirculated versions do not.

Proof coins may be ordered by the general public directly from the Mint.  Uncirculated coins are distributed by selected representatives, who make them available to the secondary market.