It measures the stability of colloidal system. It measures the PROTECTIVE power of a colloid. It measures the size of colloidal particles. All of these
Solution :Protective power of LYOPHILIC colloids is measured in terms of .gold number.. It is defined as the number of MILLIGRAMS of a lyophilic colloid that will just prevent the precipitation of 10 mL of a gold sol on the addition of 1 mL of 10% sodium chloride solution.