Ron Guth:
The U.S. Mint at Philadelphia struck very few Proof Dimes in 1854. Estimates of the total number of Proofs made in this year range as high as 50, though the number of survivors suggests a smaller quantity. This date shows up at auction approximately once a year (or less frequently), but many of those appearances are of the same coins. We know of seven demonstrably different examples (which includes Cameo examples), and there are most likely some additional coins in older auction sales. The best examples top out at PR65. Cameo examples represent about 30% of the known population; no Deep Cameo examples have been recognized yet.
Despite their rarity, 1854 Dimes in Proof are relative bargains. They are a distinctive type, they are well-made, the known examples have good eye appeal, and their rarity is high.