Only 35 proof gold dollars were minted in 1870, and some of them were probably not sold. While most advanced collectors of the era ordered proof sets to fill their runs of current coins, it is known that some prominent numismatists chose to acquire Mint State specimens instead in 1870. The actual number of proof 1870 gold dollars released from the mint is not known, but experts believe no more than 12-15 specimens are extant today in all grades.