Answer:
A precious stone, as clear as diamond. Seek it out while the sun's near the horizon. Though you can walk on water with its power, try to keep it, and it'll vanish in an hour.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.
What always runs but never walks, often murmurs, never talks, has a bed but never sleeps, has a mouth but never eats?
I scribble forms of the finest letter, And repel elements of the harshest weather. I am an arrow-aimer and a dust-breaker.
I never was, am always to be. No one ever saw me, nor ever will. And yet I am the confidence of all, To live and breath on this terrestrial ball.
What did the piece of wood say when he saw the screwdriver and screws approaching?