1900 was a big year for the Morgan Dollar and the United States as a whole -- it was the first year of the 20th century, and the beginning of the end of the Morgan Dollar at the New Orleans Mint.
That year they struck coins at all three major Mints, Philadelphia, San Francisco, and New Orleans -- with the O-Mint Mark silver dollars being some of the rarest in collecting today
And they get even harder to find in Certified MS64 condition:
(NGC and PCGS Population Report as of 03-14-2024)
1900-O Mintage: 12,590,000 vs. just 67,788 coins in MS64 or better condition
That's just 1 in every 186 coins struck.
Just 0.54% of the entire mintage!
Each 1900-O Morgan Dollar will arrive certified by PCGS as a MS64 grade coin.
