Mason studied with Dumond until DuMond's death in 1951, when he himself began teaching at the Art Students League. Mason's painting, the Resurrection of Christ, can be seen in Old St. Patrick’s Cathedral in New York. In 1962 Mason received a commission to paint eight large paintings of the Life of St. Anthony of Padua, which were permanently installed in the 11th Century Church of San Giovanni de Malta, in Venice, where his paintings hang alongside a painting by Giovanni Bellini.
Consequently, the Order of Malta conferred upon him the Cross of Merit, Prima Classe. He became the first painter to receive the honor since Caravaggio. In response to the overcleaning of the Sistine Chapel, Mason, along with James Beck, professor of art history at Columbia University, helped form the organization, ArtWatch International. The many and talented young emerging painters Frank Mason had been teaching ever since 1951 recently celebrated their teacher-mentor's 85th birthday in New York, organizing a gathering in honour and thankfulness for over 50 years of generous dedication to his students. A full length documentary film produced by Maestro films recently premiered at the Big Apple Film Festival in New York city on November 3, 2011.