There are several different soap colorants you can use…here are some of the more widely used ones!
Pigments – Once commonly mined from the earth, pigments are now usually lab created to insure stability in reproduction and purity. Mined material would sometimes contain lead, mercury or other harmful components. The two main types of pigments are oxides and ultramarines. Oxides and ultramarines work by suspension of their tiny particles throughout the soap mixture. Pigments are usually stable in high PH mixtures and tend to stay true to their color in CP or HP soap. Start with a quarter of a teaspoon per pound of oil and go up from there to get the desired color you are looking for. Mixing can sometimes be tricky; I recommend mixing with a teaspoon or more of warm water. If it is clumpy, simply break up the clumps with a pop sickle stick or spoon. You can add your color at any point. For best results, mix with your stick blender after adding the color to your mixture; this helps with fully dispersing the color and again will help with any clumps you might have missed. Just remember, If you’re aiming for a lighter trace, be sure to add in your color and still leave room for stick blending to get it fully dispersed without your soap mixture getting thicker than you had planned.
Dyes – Dyes are probably the most finicky to work with, especially in the high PH of CP or HP soap. Even “tested and true” dyes advertised by suppliers have been hit or miss in my experience with them. You want to stick with dyes that are FD&C (Food, Drug and Cosmetic) or D&C approved for skin care products or labeled as cosmetic grade. Dyes work by actually changing the color of the product you are using them in. Dyes are notorious for color morphing. Imagine making a beautiful shade of orange that goes perfect with the orange fragrance oil you are using only to wake up the next morning and it’s a hideous shade of grey! It still smells good, but not the color you were going for. Be extremely careful when using dyes and only start out using ones that have been tested in CP or HP soap. Dyes come in liquid or powder form and usage rates vary so check with the supplier you are buying them from.
Mica – Mica is what gives cosmetics, paint and other products sparkle! A natural mineral, mica comes in tiny flakes – the bigger the flakes the more surface area for light to reflect, so the more sparkly it will be. Mica works better in translucent products like clear glycerin soap but still lend a shimmer or pearlescent look to CP soap.
Soap Color Usage Rate PPO*
Alkanet root (Pink/Brown) 1 teaspoon
Annatto Seed (Yellow) 1 teaspoon
Carrot Juice (Yellow/Orange) 1/2 tablespoon
Cocoa Powder (Brown/Tan) 1/2 tablespoon
Coffee (Creamy Brown) 1/2 tablespoon
Comfrey Root (Green) 1 teaspoon
Fresh Tomato Puree (Orangey Red) 1 tablespoon
Paprika (Peach) 1/2 teaspoon
Parsley Powder (Green, Pea Green) 1/2 teaspoon
Pumpkin Puree (Orangey Red) 1 tablespoon
Rose Hip powder (Brownish Red) 1 teaspoon
Spinach Powder (Green) 1 teaspoon
Tumeric (Bright Mustard Yellow) 1/2 teaspoon
* The usage rates given are simply starting points. If you desire a lighter or darker color, simply use less or more of the natural colorant.
I tend to stick with oxides, mica and natural colorants to color my soap. Most reputable suppliers will have tested the colorants they sell and be able to provide advice on usage and expected results from using their products.