In the 1840's, the New Orleans Mint produced the bulk of Half Dollars for the nation. 1845 was no exception. In that year, the Philadelphia Mint produced 589,000 Half Dollars, compared to just over 2 million at New Orleans. A scarcer variant of the 1845-O Half Dollar is the "No Drapery" variety, caused when the fold of fabric hanging from Liberty''s left arm (viewer's right) was effaced because of over-zelaous polishing of the die.
The 1845-O No Drapery Half Dollar is at least three times as rare as the normal variant, and even more so in Mint State. None have been seen better than MS64.