Spots, speckles or splash-like deposits on, or discoloration and staining of, the paint surface. The surface may have greasy or tacky spots, be coated with particles, or feel gritty.
Foreign substances or chemicals adhering to, or becoming embedded in the paint. Common sources are:
Light staining may be removed by washing the surface with a mild detergent solution, followed by washing with a 10% Oxalic acid solution to remove ferrous compounds. Rinse, compound and polish to re-store the gloss. If discoloration and staining persist, rub down the surface and repaint