My latest experiments while still in the form of daggers are getting closer to how spears with this pattern look like. Here is the latest example. The first step is to insert the teeth using refined wrought iron into the high-carbon edge steel. For one side, I forged all the teeth and for the other side I cut them. Can you tell the difference?
Afterwards, I make the core from wrought iron and a twisted pattern-welded rod. In this case, I did a fish-mouth weld but that is not what I have seen in spears. After the core is welded, I fit both of the pieces together. The fit needs to be as tight as possible for the next welding step to be successful:
Here are the results before heat treating with a light etch:
Still far from perfect but slowly getting there.