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.
Dies half its life. Lives the rest. Dances without music. Breathes without breath.
Not born, but from a Mother's body drawn. I hang until half of me is gone. I sleep in a cave until I grow old. Then valued for my hardened gold.
It's a game played by serious people that takes place on a global scale.
You throw me out when you want to use me and you take me in when you don't want to use me. Who am I?
People take me on walks and I run and have fun. What am I?