Potassium Alum - Natural or Synthetic?
There exist two types of potassium alum sold commercially, natural and synthetic. Natural potassium alum occurs in nature as a crystallized mineral, also know as just crystals. It is found in some specific deposits throughout the world in the Earth's crust particulary in the andean alps and areas of volcanos.
Synthetic potassium alum is chemically manufactured as an effective low cost chemical. The two forms are nearly identical, except for two main differences, natural potassium alum is translucent whereas synthetic potassium alum is opaque; and synthetic potassium alum contains small trace elements of aluminum hydroxide that is left over from the chemical synthesis whereas natural potassium alum contains none.
There are various commercial applications for both natural and synthetic potassium alum. However, each has their own target market. Synthetic potassium alum is customarily applied in large manufacturing and industrial processes, such as water treatment, fertilizer production, leather tanning and more. Natural potassium alum is commonly used in the health and beauty industry where it is incorporated into product formulations, as well as being used in medical practices as an astringent and aseptic.
The reason that the two forms of potassium alum have become associated with various uses is mainly due to cost and purity. The large industrial applications do not necessarily need 100% pure potassium alum to be effective, so the inclusion of small amounts of aluminum hydroxide is not a main concern. Additionally, synthetic potassium alum is significantly cheaper to manufacture and purchase. However, commercial applications involving health, like medical supplies or beauty products applied to the skin, normally use natural potassium alum in order to provide the purest form possible without sacrificing quality for cost.