Abstract
Zashu et al. (1986) found an isochron-like high correlation between 40Ar and potassium in Zaire cubic diamonds, which appears to correspond to 6.0 Gyr. Theoretically, in view of the covalent C-C bonding of diamond and the chemical natures of electrically neutral Ar atoms and positively charged K+ ions, the partition coefficient of Ar must be much higher than that of K+ in the diamond. As a result, this effect leads to a false K-Ar ages for the diamonds. Along this line of reasoning, somewhat modified interpretations are also presented.