(a) No employer shall discriminate in the payment of wages as between the sexes or shall pay any female in his or her employ salary or wage rates less than the rates paid to male employees for comparable work.
(b) Nothing in §§ 11-4-607 — 11-4-612 shall prohibit a variation in rates of pay based upon a difference in seniority, experience, training, skill, ability, differences in duties and services performed, differences in the shift or time of the day worked, or any other reasonable differentiation except difference in sex.