Answer:
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.
I have rivers without water. Forests without trees. Mountains without rocks. Towns without houses.
I am a good state, there can be no doubt of itΝΎ But those who are in, entirely are out of it.
Halo of water, tongue of wood. Skin of stone, long I've stood. My fingers short reach to the sky. Inside my heart men live and die.
Only one color, but not one size. Stuck at the bottom, yet easily flies. Present in sun, but not in rain. Doing no harm, and feeling no pain.
You use it between your head and your toes, the more it works the thinner it grows.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?