not sure about alchemy... plz help

i have lvl 72 spear which has 5 blue magics on it, but don't have str on it... so if i put str stone on it and it fails, will my spear's other magics be decreased or deleted ? plz need answer b4 i do something stupid on it.
Thx http://forum.mmosite.com/topics/105/200712/12/4039,1.html?time=1208233744