Answer:
I am lighter than the material I am made of. You see parts of me but more of me is hidden underneath.
To cross the water, I'm the way. For water I'm above, I touch it not and truth to say, I neither swim nor move. What am I?
Good memory, skin like the sea. A great beast I am, yet vermin frightens me. What am I?
Man walks over, man walks under, in times of war he burns asunder. What is it?
Use me if you really want to see inside someone
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.