Suspect Scott #348, Used Single.
This stamp was part of a larger collection of larger collection of Washington/Franklins I bought at auction in January of 2014. The Experts Book says that this issue is often faked and can be made by adding perforations to the left and right edges of a trimmed imperforate #384 or adding perforations to the left and right edges of the imperforate horizontal coil #384H. There is no fully perforated gauge 8 ½ stock from which this coil can be made from so if the perforations prove to be genuine then the suspect is genuine.
A search of the Philatelic Foundations certificate database, as of 2/8/15, returns 399 certs with one showing as a fake coil but the associated image shows what looks like a pair of #391 (vertical coil) and a second that has an opinion of not genuine.
The suspect is 24.5mm tall. The watermark is indistinct mainly due to a large but shallow thinning in the upper left quadrant as well as other small density changes throughout the suspect.
The perforations are interesting, the left side perfs start out clipped leaving nearly three quarters of the perfs behind and the clipping continues down the edge with a slight slant to the left. About two thirds the down the edge the clipped edge stops and what looks like tearing of the paper begins leaving whole perforations. The same thing is going on with the right edge of the suspect starting out clipped leaving a quarter of the perfs with a slight slant to the left. About two thirds down the clipping stops and tearing begins removing all traces of the perfs. When the suspect perfs are compared with genuine gauge 8 ½ perfs the match is near perfect.
Conclusion: In my opinion the suspect is a genuine #393, used, large thin spot in the upper left quadrant, and partially clipped perfs from a maladjusted affixing machine.
Reference material used:
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