I recently found a recipe for dual lye shaving soap. It had 40% Sodium Hydroxide and 60% Potassium Hydroxide. My husband tried the soap and liked it. So I gave a bit out to some friends. My Husband has thick stubble and the soap worked well for him. However friends with less stubble described the soap as feeling a bit strong. They did like the feel of the soap, and felt that it gave them a good shave. But it felt strong on their skin. Since I don't have any stubble, I decided to put the shaving soap on my face and I found that it gave me a strong tingly sensation. It didn't burn or irritate my skin, but it did tingle. It felt tingly even after I had wiped the soap off. Does anyone know what might be responsible for the tingly sensation. Also, I was wondering if there is a recommended range for a lye solution that might be more suited for sensitive skin. The other ingredients in the soap were Stearic Acid, Shea Butter, Coconut Oil, Tallow, Castor Oil, and Glycerin. I used Tea Tree, Bergamot, and Lime EO.