Subject: Explain why salt water forms cubic crystals and ice is hexagonal?

I'm continuing with my science experiment. I'm freezing water and salt water 
solutions and trying to understand the crystal formation.

When salt water freezes, tiny platelets and needs of ice form over the surface 
of the liquid.  The ice crystals incorporate water, but tend to leave the salt 
behind.  The salt is excluded because salt has a different crystalline 
structure.  It forms cubic crystals (with 4 sides) whereas ice is hexagonal 
(with 6 sides).  Can you explain this in very basic terms so that I can 
understand it better?

Thank you.

MICHAEL

Re: Explain why salt water forms cubic crystals and ice is hexagonal?