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.
When there is fire in me then I am still cold. When I own your true love’s face then you will not see me. To all things I give no more than I am given. In time I may have all things, and yet I can keep nothing.
There are millions of me. I am very small but when moving fast I am deadly.
What goes through a door but never goes in. And never comes out?
A skin have I, more eyes than one. I can be very nice when I am done.
Why did the stadium get so hot after the game?