1913 Ottawa Sovereign

The second-hardest date of the Canadian George V sovereign run, and one of the keys to the series. The 1913-C has a low mintage of only 3,717 pieces, with no doubt fewer in existence—let alone in Mint State. As of January 2013, the PCGS population report claims that 122 1913-C sovereigns have been certified (in various grades from AU58 to MS64), but this number probably includes a fair amount of resubmissions. In any case, the date is RARE and very difficult to source in Mint State, particularly in MS63.