Problems Reproducing Color Samples

These two different batches of concrete were both
integrally colored “Smoky Slate,” but one is a better match
with the paint sample.

Question:
I can’t seem to reproduce integrally colored concrete countertops that match the color samples I make for clients. I’m measuring my pigment exactly. What’s going wrong?

Answer:
Integrally colored concrete can show color inconsistency for a variety of reasons, but the primary cause is lack of ingredient control. I suspect that one or more of the ingredients in each batch of concrete were not carefully proportioned.

Most often the culprit is water. Adding too much water – often to increase the workability – will alter the color of the concrete, making it lighter than a similar batch containing less water. Remember, water is the most critical ingredient in concrete, and haphazardly adding water without keeping track of the exact amount will almost guarantee an inconsistent appearance. To ensure color consistency, ALL of the ingredients, including water, must be accounted for.

The simplest way of doing this is to generate a batch report, where each ingredient amount is listed next to a check box. This is especially helpful if you are making a mix from scratch. The batch report ensures consistency in ingredient amounts, and the check boxes ensure that none of the ingredients is omitted.