Answer:
What has six faces and twenty-one eyes?
The ones who see it may go blind, Contracting the fool's madness. You have to dig to find it, Crush big stones or mine it. Wash dirt clumps in a pan and wait for it to settle, A shiny, precious metal.
I am free for the taking. Through all of your life, though given but once at birth. I am less than nothing in weight, but will fell the strongest of you if held.
I'm a god. I'm a planet. I measure heat.
What is often returned, but never borrowed/
I can only be played on a windy day
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?