There are two historical ways of soap making, one being the Castile method originating from the Italian regions of Europe and made with only olive oil. The other is more of a North American version, using animal fats as the oil.
Some soaps that are deemed therapeutic, like sulfur soaps for acne, still have a crude oil/petroleum soap base, which by itself can be a cause of skin conditions. Get familiar with the various special types of soaps, and perhaps you can come up with a natural version, like a natural sulfur-anti-acne soap.
Check back for updates on new types of special purpose soaps, such as charcoal. Consider these special purpose soaps if you are planning soap making as a small business. People love whatever is the newest trend.
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