Hamaker constants of hydrophobic minerals

The calculation of Hamaker constants of hydrophobic minerals and some selected sulphides is examined. Published data on Hamaker constants, calculated by Lifshitz macroscopic theory, are found to correspond to results obtained using Israelachvili`s equation, which is used to predict Hamaker constants of minerals across a vacuum, where the refractive index in the visible and the main electronic absorption frequency in the ultraviolet region are known. These parameters can be calculated for most ore minerals from published data on reflectance. 23 refs., 4 figs, 2 tabs.