Sounds like a good idea.
I had to make it permenent, but I removed the capacity for items of +1 enchantment.
- Devon
Glassteel
Transmutation
Level: Sor/Wiz 6
Components: V, S
Casting Time: 1 minute/lb. transformed
Range: Touch
Target: 5 lb. of touched glass/level
Duration: Permanent
Saving Throw: None
Spell Resistance: No
Glassteel is a magical substance created by arcane spellcasters from normal glass. While remaining natural glass in almost every way, glassteel is as strong, and heavy as steel, perfect for making windows for vehicles such as deep-sea craft, siege vehicles, and other structures.
Spells that affect metal or iron (such as heat metal) do not function on glassteel. Spells that affect glass do affect glassteel. Using this spell with a glass-related Craft check, the character can fashion glass items that function as steel items. Thus, glass armor and glass swords can be created that are as durable as their normal, steel counterparts.