Riddle #149

Question: I can be used to build castles,
but I crumble in your hands.
I can help a man see,
and am found all around the lands.

What am I?

Question: What tastes better than it smells?

Question: What goes in the water black and comes out red?

Question: What loses its head in the morning and gets it back at night?

Question: What two things can you never eat for breakfast?

Question: What asks but never answers?