Workpiece surface area determination

A process for determining the surface area of a workpiece in which the entire surface of the workpiece is smooth which comprises:

• forming a removable coating of a metal or a metal compound on the entire workpiece surface by immersing the workpiece in a coating composition to obtain a coated workpiece, removing the coating from the workpiece surface by covering the coated workpiece with a coating-removal composition, at least one of the compositions selected from the group consisting of the coating composition and the coating-removal composition being a composition in which mass transfer is practically diffusion controlled, and comparing the quantity of coating removed by the coating removal composition to a standardized quantity of coating removed from a sample of known surface area, said standardized quantity having been obtained by coating the sample and removing the coating from the sample under the same conditions that were used to coat the workpiece and remove the coating from the workpiece.