1940 Mercury Dime. Proof-68 (PCGS). One could spend years searching and not find a more beautiful Proof Mercury dime of any date than this Ultra Gem 1940. Both sides are peripherally toned in exceptional steel-rose iridescence that is more extensive on the obverse. An intermingling of other vivid colors is also evident within the dominant toning -- lovely! Fully struck, as befits the method of manufacture, with silky smooth surfaces that approach numismatic perfection.