Proofing stones were used to check the flatness of an engraving plate. This stone dates from 1923, and has on it a reference to an around the world voyage of the young children of the rich, an effort to educate and improve the knowledge the days youth. Candler was the owner of Coke Cola.

There are many other 1923 stamps. One is the California Insurance Company, that paid out big time after the 1906 San Francisco Eartquake and fire.