Mary Cain was a daughter of noted potter Christina Naranjo, and grand-daughter of SaraFina Tafoya. Mary was an innovator and pottery matriarch in her own right, as she began a family of renown Santa Clara potters, including daughters, Tina Diaz, Joy Cain, Linda Cain, sons Billy Cain, and Doug Cain, and granddaughters Tammy Garcia and Autumn Borts-Medlock.
Mary was known for her deeply carved pottery surfaces with a high polish finish on the pottery. Mary used the Santa Clara Pueblo traditional methods of hand coil construction of the pot, and shaping and sanding to smooth form on the pot, then applying a fine slip coat and polishing with a stone to a high sheen. She fired traditionally in an open fire for red pottery, and manure application to apply the smoke for a black finish.