Difficult
It is in the rock, but not in the stone; It is in the marrow, but not in the bone; It is in the bolster, but not in the bed; It is not in the living, nor yet in the dead.
Difficult
The land was white the seed was black it'll take a good scholar to riddle me that. What is it?
Difficult
Thousands lay up gold within this house, But no man made it. Spears past counting guard this house, But no man wards it.
Difficult
Whoever makes it, tells it not; whoever takes it, knows it not; and whoever knows it, wants it not. What is it?