A quality bar of handmade natural soap will often "sweat" in humid weather due to the high content of natural humectants like glycerin which readily absorbs moisture from its surroundings.
People think of henna as a hair coloring product. However, henna is a deep conditioner that seals in moisture, tightens the cuticle, enhances body, adds loads of shine, and makes hair silky soft.
All real soap is made with lye (sodium hydroxide). During the saponification (soap making) process the lye combines with the fats or oil to make soap. There is no lye in a finished bar of soap.
It is impossible to make real soap without lye and organic lye does not exist, so there is no such thing as a "100% organic" soap based on the 3-tier system of the USDA National Organic Program.