So Frostburn list Blue Ice as an Exotic material.  It weighs half as much as iron and can be forged, shaped and utilized as if it were iron. (
Very useful to keep your beer cold!)

When forged into a slashing weapon it has a +1 enhancement bonus on damage.



If I were to crate a masterwork blue ice long sword, would it be the same as +1 blue ice long sword? (Minus it being magical) +1 to attack and +1 to damage?

Does this enhancement **stack** if the weapon were to be magical, say a +2 blue ice long sword.  Giving a +2 to attack and **+3** to damage?

*(Please add reference, preferably rulebooks)*