Proof 1905 Half Dollars came out in a limited mintage of only 727 pieces. The vast majority of survivors are Brilliant Proofs, usually in a range of grades from PR61 to PR66. Cameo Proofs are very rare -- even more rare than the previous year. Deep Cameo Proofs probably do not exist, just based on the methods the Mint was using in th early 1900's to strike Proofs. There are a number of wonderfully toned, high-end examples of this date, though anything PR67 or better is a real prize.