$20 Saint-Gaudens Gold Coins MS 66
MS 66 is the contraction for the denotation "Mint State Grade 66" within the Sheldon grading system invented by Dr. William Herbert Sheldon in 1949. The top of the Sheldon scale is a perfect score of "70", and at one time a MS 66 $20 St Gaudens' gold piece may have been a true 70, however over the years a soft gold coin will sustain a nick or scratch or two, and this is enough to cost the coin a few grades. It should still be noted, however, that an old Saint-Gaudens $20 piece in MS 66 will trade at a premium over the spot price of gold.
Specifics of the Grade
A MS 66 $20 Saint-Gaudens gold piece in MS 66 will have full "Mint luster" or a rich golden shine. Few marks or scratches will be present, and they will be small and in unobtrusive areas of the coin's designs. Any flaws from the minting process will require magnification and a trained eye to discern. A $20 Saint-Gaudens Double Eagle in this condition is not only beautiful, but difficult and more costly to come by.