Density (3.5e Spell)

Improve Density: shrinks the object two size categories; and improves the hardness by 1 per three caster levels (up to +4 harness at 12th level). But the object's hitpoint total remains the same.

Reduce Density: enlarges the object two size categories; and reduces the object’s hardness by 3 (to a minimum of 1), and grants a +3 competence bonus to sundering the object and damage rolls. But the object's hitpoint total remains the same.