Because they include a proof Mercury dime as well as a proof Walking Liberty half, early proof sets such as these are always in great demand. Mintages range from just 3,837 sets issued in 1936 to 21,120 made in 1942 and, because many ended up in circulation, only a fraction of those amounts survive today. Adding to the demand is the fact that there were no proof sets issued between 1943 and 1949!
Current Metals Market:
Gold bid 1306.40 , chg +3.10 ; Silver bid 15.35 , chg +0.03 @ Mar 19, 1:32:29 pm EST