There are so many different types of colorants that it can be a bit confusing for both beginners and long time soapers. So hopefully this will break it down for you and make this colorful world easier to work in!
Yellow - Annatto, Saffron, Turmeric
Green – Chlorophyll (a green pigment found in almost all plants), Spirulina ( a nutritional supplement )
Brown - Cocoa Bean (pods, shells, stems), Cocoa Powder, Fermented Tea
Red - Paprika (can be irritating )
Purple - Alkanet Root (for Cold Process soaps only)
Though nice for marketing value, they can be difficult to smoothly blend in and are expensive.
They are manufactured in a lab, are not natural but are generally very easy to use and give a wide range of color.They are very highly concentrated. They mix in very
smoothly. They work very well in Melt & Pour soaps, but can bleed colors. However they are not stable in alkaline products like cold process soap.
These I consider as part of the FD&C colorants category. Mainly because mica is a natural product, that is mined, then its coated with FD&C colorants, to achieve the color desired. They work great in clear melt and pour, because of the lovely shimmer they have. Now you can use micas in cold process soaps, they are smooth and are easy to work with, BUT, they can morph and change color in a high ph environment, so personally I don’t use many of them.
Pigments, Oxides & Ultramarines:
Now as a mainly CP soaper, I myself prefer these over everything else. They are the most stable in high ph environments. These however, are not all natural. They used to be mined, but the FDA banned their use due to massive impurities back in the 70`s. So now they are all produced in a lab where they are as pure as possible with no toxic metals as the old mined ones contained. These are great to work with, no morphing and just mix well in a bit of oil or vegetable glycerin to make smooth before adding to your soap.