Silly Brit. It would almost be impossible to get a huge, single mass of pumice to carve out a ship. There are plenty of stoners, though. Boats and ships have been made from concrete for many years.
My dad rendered a Ferro cement hull of some kind of sailing boat when I was quite small...they have to keep it soaking wet and covered in sacking and keep the sacking wet for many weeks to cure it slowly.
And just do you know......If your only tiny like me.... every Thing looks huge to begin with...!! Hehe
Not Sure 