Answer:
They're up near the sky, on something very tall. Sometimes they die, only then do they fall.
A house of wood in a hidden place. Built without nails or glue. High above the earthen ground. It holds pale gems of blue.
The stack just might be sent all over. Full of what's new, yet it's nearly obsolete.
Big as a biscuit, deep as a cup, but even a river canβt fill it up. What is it?
A certain wizard resided in a city made from this gemstone.
You can always find me in the past. I am created in the present, but the future can not change me. What am I?