Small brass solderig in helmet

[verdammt]

...plugged holes in the helmet with a light yellow substance.

So it's not metal?

[Anderson]

Looks like someone has plugged a hole with brazed silicon bronze. It's a relic helmet so probably someone was aiming to restore it, maybe fill a hole and rust pitting and paint it. But the brazing was a far as it went.

[verdammt]

Unfortunately, the pictures didn't show that the helmet has a really big rusty hole on the top... so i don't think the restoration of a helmet in such poor condition would have started by filling a small pit.