I think its white maple that has a ripple grain that makes it exceptionally hard to split. I have a couple of planks laying on the ground to cross a small creek in my yard. They’ve been laying on the ground for around 15 years and are still rock hard.
When I worked at the saw mill we build all our catwalks out of white maple. We had to use a nail gun to get the nail started then pound them in with a hammer.
Well, if that’s so, this is a gem of an axe. He should sell many units. 15 years. Very good...