Where does that much volcanic rocks go??? Nearly the size of Belgium. This could be skimmed to make ‘roman concrete’.
Has to be crushed first.
1,000 kilometers (620 miles) northeast of Auckland. That is outside of New Zealand EEZ. Who owns it?
ISA (International Seabed Authority) might claim it, but it is not seabed because it is floating on the surface of the high seas.
There is so much of it, that anybody can do with it whatever …
I know it happens occasionally; a chunk of rock with enough air in it to float drifts around the ocean until it gets waterlogged. Somewhere, in another thread, there was talk about simply water proofing one as-is and moving in. I like your idea better. If you put the processing equipment on the rock itself you could work from it until you had enough artificial land to move onto.
As far as legal ownership I doubt you would get much of a fight from anyone. Most established nations have rocks. and all you have to do is tie it up in court for months (not hard to do) and work fast.