David Hall: Technically a variety, but long collected as part of the main set, the 1917-D on Obverse Walking Liberty half dollar is a low mintage semi-key date that's relatively scarce in circulated grades. Mint state examples are very scarce and Gems are rare. Of the four Denver and San Francisco issues of 1917, the 1917-D Obverse is the least rare in mint state and Gem. Strike is decent for the early dates in the series, which is of course somewhat more shallow than you find on the later dates. Luster can be white and somewhat satiny.