The 1858-S Dime is a great date in a series full of rarities. The 1858-S Dime has a mintage that is identical to that of the 1859-S Dime (60,000 coins), and both dates boast the smallest mintage of any of the U.S. Dimes from the 1850's. Even in low grade, the 1858-S Dime is a recognized rarity, but in Mint State, it is virtually impossible to find one, let alone a nice one. The runaway star for this date is the PCGS MS66, formerly of the Eugene Gardner Collection and the price-record holder of $88,125. A strong candidate for second best is the Eliasberg example, graded MS64 in 1996, but not seen since then (to the best of our knowledge).
Researcher Jerry Fortin identified three different die varieties for the 1858-S Dime, which is a surprisingly large number for such a small mintage. According to Fortin, the three varieties are of roughly equal rarity.