Ron Guth:
In a survey of the members of the Liberty Seated Collectors Club, published in the March 2008 issue of the Gobrecht Journal, the 1842-O Small Date Quarter was ranked sixth among the Ten Greatest New Orleans Seated Coins: "This is one of the key dates in the Seated quarter series that is very difficult to find, especially in high grade. Only one mint state specimen was reported in the recent Seated quarter census that was published in Issue #100. An example graded NGC MS-63 appeared in the Heritage auction at the Denver ANA convention during August 2006. There was generally strong support for this issue with 59% of the respondents placing it in the 3rd through 9th position in their listing."
The afore-mentioned NGC MS63 sold in 2006 for $74,750 to Eugene Gardner. When this coin reappeared on the market in 2014, it sold for $55,812.50. It remains the only Mint State example known of this date.