This causes written words on any surface to simply boil away to nothingness, regardless of what they're written with. It cannot erase engravings, however.

Create (Writings and Drawings, Small Category) 1 [12] 
    Destruction Only [+0%] 
    Reduced Fatigue Cost 2 [+40%] 
    Based on Activation Roll [+5%] 
    Magical [-10%] 
    Spell Components [-20%] 
        Must say "erase" in Latin 
        Must gesture with hands 
Level 2 [23] 
    Increase Create by 1 level [+10 base] 
Levels 3+ [+11.5/level] 
    Increase Create by 1 level [+10 base]