Looks like corian, so plastic. So long as those cuts don't extend past the basin, it can be fixed with a router and a couple bits. If they do extend past the basin, probably bottom right, then you could fix it with resin and make it pass anything but a close inspection with some skill.

It might be the type of basin that drops in from the top, which would be easier to fix and would be more likely to hide the bad cuts under the flange.