What This Coin Looks Like (Obverse, Reverse, Mint Mark Location, Special Features, etc.): There were two major varieties of the 1854 Liberty Head $20 Gold Double Eagle. One variety features a small 1854 date on the obverse of the coin (depicted above) while the other variety features a large date. It is fairly easy to distinguish the sizing difference of the date - the large date is much larger and the numbers are closer to the liberty bust (especially the number "1" in the 1854 date). The difference between the 1854 Small Date vs Large Date is depicted below in the example comparison image (Source of example images is courtesy of Heritage Auction Galleries):
Coin Value Chart: Typical Coin Prices, Values and Worth in USD based on Grade/Condition