Kicking this thread off again, and with a rather nice hand forged axe. Early Googles indicate possible late 19thC but am waiting to hear back from a few enquiries.
This was found about 40cm down in a nearby beach last week after some sand had shifted. Would normally have been out of reach or too scratchy to chase. Gave a really rich tone rather than the usual iron grunt which is why I followed it.
Still needs a fair few hours in the passivation bath, the hard work has been done though so it’s back to the low current for cleaning up before treating and sealing with microcrystalline wax.
Any time you lift ancient iron, it’s important to keep it wet until you can treat it, then it needs to be electrolysed and treated to prevent further (rapid) decay. To ensure a good electrical contact with the object, I drill a small hole and bite an old tap in for a couple of threads, then clamp the electrode to this. As passivation only works in direct line between electrodes, a tin can lined with green scouring pads (to prevent accidental shorts) works excellently with a 360° coverage.
This is progress so far…