Jeff Garrett:This date is the second rarest Indian $10 after the 1911–D. The 1913–S is rare at any level of Mint State and difficult to locate. Prices for the issue rise sharply at every stage of the Mint State ladder. Unlike other San Francisco issues, the strike is usually at par or better. The Smithsonian collection contains a single AU example. Two fantastic coins of the date exist, both grading MS 67. The first coin was part of the legendary collection of Harry W. Bass. That coin last crossed the auction block at $143,750 in 2004. The Ex. Robert Kruthoffer specimen sold for $54,000 in 1981; a respectable price for the time. It resold in 2007 for $299,000.