True - The absorption is a non-factor, especially considering the small amount in a typical mix.
As an example, in zero slump concrete the absorption of the pigment is not enough to dry out a mix. Due to the large volume of aggregate used, a wet period can raise the moisture content of drained sand to a point where the absorption of a dry pigment will not dry out the mix to a level where an acceptable product could not be made, but the strength went up over the target, but the tolerances were lost and the color changed. This is based on millions of sf of products produced annually.
Elimentis may be the supplier, but when it comes to synthetic oxides, the different colors required include factory blending of various basic color oxides since the global processors are limited.
The major use of pigments in concrete world-wide is in zero slump concrete products where moisture control is important and the products are subjected to performance testing and not theoretical mix designs because the manufacturing systems are the controlling factor.
If you are using any color with a blue or green "tint", chrome oxides (pricey) may be used instead of iron oxides that are limited to yellows, reds to blacks with no cool tones. Avoid carbon based "pigments" for blacks and grays.
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