NOTE 1 A high content of copper in the alloy can lead to increased dissolution of the basis aluminium.

NOTE 2 If the thickness is known with sufficient precision (for example, using the method specified in ISO 2128), determination of the mass per unit area (surface density) of the coatings will enable its apparent density to be calculated. Conversely, if the conditions of application of the coating and its density are known, the determination of its mass per unit area (surface density) can permit calculation of the average mass and an approximate evaluation of the thickness (see the Note in Clause 6).