Patent ID: 8882908

Claim:
A method for reverting uncured colored concrete in a vessel to gray, the colored concrete comprising gray concrete and a pigment formulation at a loading, the method comprising: determining an amount of red pigment, an amount of black pigment, an amount of yellow pigment, and an amount of green pigment in the pigment formulation; and adding a reversion pigment mixture to the colored concrete in the vessel, the reversion pigment mixture based on the amount of red pigment, the amount of black pigment, the amount of yellow pigment, and the amount of green pigment, wherein the reversion pigment mixture is at least one of the following: (1) if the amount of red pigment is greater than 15 wt-% of the pigment formulation, then selecting the reversion pigment mixture to revert red to gray, (2) if the amount of black pigment is greater than 15 wt-% of the pigment formulation, then selecting the reversion pigment mixture to revert black to gray, (3) if the amount of yellow pigment is greater than 20 wt-% of the pigment formulation, then selecting the reversion pigment mixture to revert yellow to gray, and (4) if the amount of green pigment is greater than 10 wt-% of the pigment formulation, then selecting the reversion pigment mixture to revert green to gray.