KROMATIKS pigment pastes are to be used at 8% and 12% in clear polyester gelcoat and at between 3% and 5% in clear polyester backing resin. All the colours are manufactured to a tolerance of CIELAB D.E.0.5 from a master standard. Uniformity of the colour can be affected by: Batch variation of the colour of the clear resin or gelcoat particularly with paler shades. Incorrect weighing of the colour paste. The addition must be done by weight due to variation in specific gravities of the colour paste.