1910-S $20 Saint-Gaudens Double Eagle NGC MS64 CAC. From Jeff Garrett and Ron Guths, Encyclopedia of U.S. Gold Coins, we cite: “The vast majority of 1910-S double eagles struck were melted during the 1930s, a time when all gold coins were called in by our government. Those that did survive were squirreled away in small collections or happened to end up overseas. A couple of small groups were discovered in European banks or El Salvador.” Going further: the Akers-Ambio Handbook of 20th Century United States Gold Coins characterizes the 1910-S as “a common issue in all grades below MS-65,” and recognize better examples are scarce and more elusive than high-grade pieces from the immediately surrounding mint-marked issues.
The high-water mark occurred for a PCGS MS67 back during the FUN show of 2015, realizing $88,125. This coin is apparently pretty well known to specialists, as ten years earlier the same company sold it out of the Philip Morse collection for $51,750. Prior to that, it was the property of Thaine B. Price and Louis Eliasberg.