I can't really advise you on making a sea salt bar if that's the way you'd like to go, LissaLoo, but I did want to share some ideas ....
Firstly, if your customers daughter has severe acne, she probably should see a dermatologist. Untreated acne can leave nasty scars, both physical and emotional. So I'd want to be sure that appropriate medical care is not delayed if its needed. If the acne is not severe (or cystic), then probably a good cleansing and moisturizing regimen is all that she needs.
General principles for facial soaps to improve acne are:
Keep the soap mild and gentle, with a high proportion of OO - which will need a long cure. A high percentage of CO can over cleanse, and strip the skin's natural oily barrier (sebum) leaving the skin dry. This results in the skin overproducing oils to try to replace the sebum layer, which exacerbates the acne.
Additives like activated charcoal or a clay (perhaps pink clay if her skin is not oily) are useful because they adsorb impurities, so provide additional gentle cleansing.
Other additives worth considering include carrots, which are rich in vitamin A (use carrot purée instead of water to make your lye solution), honey, and herbs with antibacterial properties (thyme has been shown to have an antibacterial effect on the bacteria which cause acne - although as soap is a wash-off product, it's difficult to say whether a thyme soap would be active in reducing Propionibacterium acnes) or even calendula petals or infused oil.
And remember that you shouldn't make any claims that your soap (or toner, moisturizer, etc) treat acne ........ as that would push it into the realms of a drug.
Sent from my iPad using Soap Making
