Pure Castile Soap.
Ingredients: Olive Oil, Coconut Oil, Lye, Water, Essential Oils
This bar has lemongrass and other citrus essential oils. Nice clean fragrance.
How does soap work? Just a quick explanation since I used to teach science! There are two types of molecules to worry about here: hydrophillic (water loving) and hydrophobic (water avoiding). Most dirt, grime, and grease that will not simply rinse off is because it is hydrophobic and will not mix with water. Think about oil floating in water = hydrophobic. Your skin is made of non-polar lipids (fats/oils). Grime and grease made of lipids sticks to other lipids (your hand). Soap is made through a process called saponification. It involves lipids (fats/oils) and lye (NaOH). The lye changes the oils in the soap to a new molecule that is essentially a non-polar lipid on one end allowing it to stick to lipids (the grime and grease on your skin). The other end thanks to the lye is now polar. An ion with a charge that can stick to water (think magnets here). If one end sticks to the grease/grime and the other will now stick to water it can be washed away! This is why you need soap to wash off oil and grease and can not simply use water alone. Thanks soap.