Maximiliana Montoya (1885-1955), better known as Anna, was the eldest sister of Maria Martinez. Like Maria, Anna was making beautiful polychrome pottery in the early 1900s. However, Maria almost never painted anything so Anna painted for her until Maria married Julian and he took over the painting. When Maria and Julian started making black-on-black pottery, Anna was one of the early learners and adopters of the technique.

Anna's husband was Crescencio Martinez, one of the founders of the San Ildefonso School of watercolor artists. He painted many pieces for Anna and they were encouraged and supported by Dr. Edgar L. Hewett almost as much as he encouraged and supported Maria and Julian. After Crescencio passed away in the flu epidemic of 1918, Anna painted all her own pieces and soon became an accomplished painter in her own right.

Anna worked with Maria for many years, sometimes polishing pots, sometimes decorating them. Maria often commented on how "everyone bothered" Anna to "put design" on their pottery. Anna also developed her own distinctive forms and shapes, including an elegant "teardrop."