Abstract During the last half of the twentieth century, the argon-argon method of dating geologic rocks and formations became very popular. This method replaced K/Ar as the method of choice for many types of rocks. This paper explores the fundamental mathematics of the argon-argon dating method and evaluates the impact of the assumed date of the "standard sample" on the calculated argon-argon date. A method for testing the validity of an argon-argon date is proposed with example evaluations. The analysis in this paper shows that when the results of dating studies are validated against the foundational equations upon which the argon-argon dating method is based, the "older" the standard sample the greater the results differ from the foundational equations. This seems to indicate that the assumed age of the standard sample has an effect on the calculated age of the unknown sample. The paper proposes a way to further investigate and quantify the effect of the assumed age of the standard sample. (available to the public)