You can eat and drink from me, but I'm hard to crack.

I am often found standing on a block of wood. I get hit while changing other's shapes. When they hit me I sing.

I am hard but brittle. I am liquid when left alone. My good side is always sunny.

Brush my teeth with grease and oil, not water and paste Put me with my brethren; teeth touching, a few at a time, to move giants We grind our teeth endlessly, so your machines may live

Cloven, clever piper, Eponym to freezing shock, A name long cast in iron, Fits well among the flock