In 1859, collectors in the general public embraced their ability to purchase coins directly from the U.S. Mint. In so doing, they hit every denomination hard, ordering a then-record number of Proof coins of all denominations...even Proof gold. The Phildelphia Mint produced 800 Proof Dimes in 1859 and presumably sold most or all of them. Today, numerous examples survive in a wide range of grades and formats. Brilliant Proofs are the most plentiful format. Cameo Proofs represent approximately 20-25% of the total population of all Proof 1859 Dimes. Deep Cameo Proofs are exceedingly rare.
Most Proof 1859 Dimes grade out at PR64. Gem examples above PR65 are quite scarce and anything above PR66 is a major rarity.