Oh boy! These axes have been like land mines lately! As mentioned in other posts, the identification of an ax as a boarding tool versus one that is a fire implement becomes difficult unless we have an example that either (#1) has provenance, (#2) is government-marked or (#3) of the EXACT pattern of naval examples. With this ax head, we have both good and not-so-good indicators of possible naval use.
First off, it displays good age. The head appears blacksmith made, but could also be an early trip-hammer casting post 1830's. I like the small, round eye. The earlier, pre-1800 examples usually have slightly larger eyes, but the mid/late 19th c. Brit boarding ax patterns have an eye exactly like this one. The original haft on the older models would have been this length, but typically had a ball at the end of the haft. The spike wedge looks right, with its almost beak-like curvature and design. The pitting on the head seems plausibly caused from years at sea in an environment of 'salty air', thus the reason most iron items were primed/blackened. Yours has this blackening.
Now, I'll play devil's advocate. The blade edge on this piece doesn't quite fit either the early or late Brit pattern of boarding ax. The early, pre-1800 examples slightly flare both up and down (double-bearded), whereas the later Brit (mid/late 19th) elaborately flares outwards. Despite the fact that boarding axes were weapons, in all the examples I've seen on the Brit patterns, their langets were all relatively short in length. Yours are much longer. Langets on Brit boarding axes are rounded with the haft, yours more flattened to the piece. Brit examples langets usually have a rounded end where they point towards the butt. Yours is not as rounded. The ordinance mark on the haft appears genuine. The question is, is the haft replaced at a later time or when the ax was made?? It is just too hard to tell for me. If it is original to the piece, it is a non-typical haft for a boarding piece. The fine pitting does look like 'maritime' rust, but casting flaws and normal oxidation sometimes does as well.
Soooo...(
), where does this leave us? It could be a private purchase item used on many of the merchant class to defend against hostile boarding in the era of Fighting Sail. It is not the classic government issue based on what I've listed above. Perhaps others might offer their opinions on the piece? Gene? Broadaxe? Kronkew? Where are you, buddies?! I'm going to stew it over some more...