PCGS - Just because we at PCGS have been fortunate to discover and attribute, in just the past couple of years, new Liberty
Seated half dollar die pairings for the 1843-O, 1850-O, and 1867-S, does not mean a new discovery is in any way diminished. Within a few months of each other, we have had the opportunity to attribute not one but two new die pairings in the Liberty
Seated half dollar series, the first involving an 1850-O and the second, profiled here, an 1855-O. Bill Bugert and his books as well as Mike Perkins helped confirm this new variety.

This 1855-O die combination took a few more looks than our last discovery, the 1850-O WB-20. The obverse appears to have "cruddy" lumps in the drapery below Liberty's right elbow, similar to those on Obverse 2 (but different than those on Obverse 7). The reverse has a matching die crack (between S and O) like that on Reverse L. The tricky part with this reverse is the die state, which appears to be advanced. Luckily, we all were able to spot the spots between the right wing and the "E S" and pick up the die crack between the "D S." After some additional ruminating and double-checking, we all concurred that it was the die state that made the difference and that, in fact, we had a new die pairing for the 1855-O (WB-20).
If you are assembling a complete set of 1855-O Half Dollars by die combination, the WB-20 adds one more challenge before completion. With Obverse 2 showing up on WB-2 and Reverse L for WB-15, this new discovery, especially in the later die state of the reverse, may provide a clue to the die-emission sequence of these three die pairings of this date and mintmark.
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