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  Unique Branch Mint Proof 1891-O Seated Liberty Dime NGC PF 66 Unique CoinsSome of the most famous U.S. coins were struck under mysterious circumstances and the story behind their production adds to their rarity, prestige and value. Examples are coins struck in proof where only one example is known, a special specimen striking struck with polished dies, while others are patterns, trial strikes, or mint error coins. Here is the only known 1891-O Seated Liberty Dime struck in PROOF! Authenticated and certified by NGC as a Proof 66, this unique Branch Mint proof is a world-class rarity.   |
