I use nori seaweed that I buy in sheets at an ethnic grocery store. I think this is the type of seaweed that is used in making sushi. I take one or two of the seaweed sheets and tear them into small pieces and then use part of my water to soak the seaweed in. I add this at light trace and pulse with a stick blender to evenly distribute the seaweed. The seaweed will color the soap a light green with dark green/black flecks in it. I just use my regular recipe with the addition of the seaweed.
The “nori” seaweed that is used in sushi for the maki rolls is great for seaweed soap since it is already dried and crumbles easy. You can infuse it in the EO you are going to use for awhile and that helps bring out the color. I’ve used eucalyptus with the seaweed and it turned out nice.
I make a seaweed soap and it is quite easy to do. I just use my standard soap recipe, and at light trace I add blenderized, cook nori that I get from the health food store. To cook it I just follow the ingredients that were on the bag. I use an ocean FO to scent it and it is great!
I’ve tried 3 types of seaweed/algae in CP soaps: crumbled nori, powdered spirulina, and powdered kelp. I like nori the best. Nori creates pretty dark green flecks in a very pale green/cream-colored soap. Spirulina makes wonderful deep blue-green M&P soaps, but my CP soaps with spirulina eventually lose their green color during curing. (In CP soaps, adding more spirulina might be the answer?) And kelp makes a long-lasting green color in CP soaps, but kelp-colored soaps are kind of a pale pea-soup-green (some people love it; some don’t). For an all-natural “sea” scent, one book recommends Rosemary EO. I didn’t like it at first, but it’s growing on me… can’t say it smells really ocean-y, though! :-)
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