Settlement of pigment to the bottom and failure to re-disperse. CAUSES: Insufficient stirring during storage. Storage for long duration or under excessively warm condition. Excessive dilution or dilution with unsuitable materials. SOLUTION: Store as recommended by manufacturer. Avoid direct sunlight and long storage. Dilute with appropriate thinners as recommended by manufacturer. Stir paint to a homogeneous consistency. Employ mechanical stirring for heavy settling.