I am almost 100% certain that is an electrically welded axe. The welding was done fron either side of the blade, creating a classic V-shaped filling of rod/wire. You can also see where the two V's touch in the centre, this is bad in welding circles coz it's not 'full penetration' and is a sign of a potentially weak joint, though the amount of weld material (and surface contact with the metal either side) is massive enough that its not likely to be a problem. The side view also has a dark line (void) running about 1/4" from one side to the other, this is the edge of a weld bead where it has not been fully filled by the next bead along. The colour of the band looks very low carbon compared to the stuff ether side, suggesting that the material is a formerly molten blob of mild steel (loses carbon in the process), the sides are still likely mild though unless the blade is much darker than the eye side
I know of at least one 'historical' smith who makes stuff for reenactors and does that when making axes. Rather than punching the eye through a solid block and then drawing the blade from it, or wrapping and welding (even the asymmetrical method mentioned), this bloke starts with heavy walled pipe and welds a bit of plate to it, then forges the blade from that and drifts the eye to the right shape.
If the welding is good and he normalised the welds well (which would happen during the forging anyway), then the axe should be solid enough to not fail on you. But, apart from the fact that it is a crummy cheat of a method that looks ugly he has most likely welded a mild steel blade to a mild steel socket. So unless for some reason he went to extra lengths to weld on spring steel as the blade, that thing won't hold an edge (also, if he can't won't make the axe properly, what do you think the chances of him using the right steel and then heat treating it properly are?). He could have constructed the head like this and then firewelded a good steel edge on, but then why not fireweld the eye too? If its an electrically welded edge (seen that too!), then you will see the same discolouration across the blade where the edge is fitted
if it were a fire weld then if you can see anything at all then it will appear as a fine white line (flux left in the weld zone leaching out) or a fine dark line (a flaw where the pieces haven't actually joined). This will appear down the cetnre of the blade when viewed from the top on a conventional bowtie construction, or stating in the middle at the eye and drifting off to the blade a couple of inches down if asymmetrical. Wrought iron is fibrously looking like wood and the welds tend to blend in much better than mild steel, but you can see the way the fibres change direction on a polished piece (like a patch on a sheet of plywood).
welding an eye is not that tricky, I've taught a blind man to do it because it was more likely to succeed for him than punching. With wrought iron it is also less likely to fail during manufacture than a punched one too actually. If a man is calling himself a smith then he can fire weld, no ifs no buts, it is just another skill that you need. wrapping and welding an eye is faster and less expensive than electrically welding a tube on. If I made an axe by the traditional methods then the eye would take 10mins to punch tops, 20mns to weld (assuming I'm not doing a pretty job as Jim Austin does, but even then, not too long) or maybe an hour to do the 'modern way (you have to scarf the joins, weld, clean the beads of scale, keep welding until full, grind off the excess, normalise the weld so it doesn't crack when I then dress with a hammer in the forge). The old methods only consume a little more fuel and steel in the making, the modern one consumes fuel, electrodes/wire (likely 4-6 rods!), grinding discs, electricity as well as being much worse for you health! Sod that I'm a blacksmith, I'll make the eye the old fashioned way!
