From what I understand, most of the KOH out there is between 90% and 95% pure. The only way to be sure of the purity is to ask the company you bought it from.Songwind brought the discussion here that started over at:
I re-read these two threads today, and I found a huge question! The Soapcalc numbers on the page 5 I linked to, did not check the 90% box on the KOH. Now I don't know if the KOH I have is considered 90%?
Are most KOH 90% or is 90% rare?