When you work with Melt and Pour soap, you typically melt the soap base, then stir in the color and fragrances. If, however, you overheat your product, the heat can negatively change the nature of the color. The most common problem is with speckling. Speckling is flecks or clumps of color that will not dissolve into the soap base and no amount of stirring will help. The above photo is a perfect example of "color speckling".
The hotter the medium, the worse the speckling. You will not know if your color is sensitive to excessive heat until you run into the problem. If you do, try working with lower temperatures. We have found that the powder pigments present the greatest potential for speckling though it can occur with certain liquid gel colors as well.
Before adding any color (gels, liquid, or powder) we suggest allowing the soap to cool down to a temperature of 140 degrees. If you can comfortably dip your pinkie finger into the melted soap, it's a good temp for adding color. GoPlanet's Neon purple and Chromium Green Oxide have been known to speckle when we have added the color at high temps. If using these colors, allow soap to cool until a thin skin of soap forms on the top. Break through the skin to add the color and stir until you no longer see any color flecks. You can then reheat the soap to a pourable temperature.
Use patience when working with colors. Keep in mind that colorants are raw materials and there can be inconsistencies with their use, i.e., speckling or dots of undispersed color. With patience and the right pouring temp you can overcome the speckling issue.