# Is it safe to mix potassium alum powder with magnesium oil (made from water and magnesium flakes)?

Will mixing these two together cause a reaction of any sort? If so, is it safe and is there an order in which one should be added to the other?

Potassium alum is $\ce{KAl(SO4)2*12H2O}$, the compound that you use to stop bleeding after a bad shave.
If you are not sure and you have to do the reaction, try it with small sample of $\ce{Mg}$ such as one flake. $\ce{Mg}$ flakes should react in water and will react with potassium alum.