Answer:
Sometimes black, sometimes white, I have veins but no blood
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.
Though blind as well, can lead the blind well.
It is worldwide, but once only a spider could weave one
They make no sense at all, In them you either fly or fall. They make you do it all. Their need is biologic, but they are most illogic. They are not real but still can be achieved, If they are just believed
The warmer I am the fresher I am.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?