This paper attempts to refine the classification of Mexican majolica ceramics from Spanish-Colonial sites using chemical data obtained by neutron activation analysis. The ceramics examined come mainly from excavations in Mexico City and from the Santa Catalina de Guale Mission site, St. Catherines Island, Georgia. The majolica types from these sites include both Spanish and Mexican examples and range from sixteenth to late seventeenth century. A rationale for the chemical classification of Mexico City and Puebla production is proposed.(A.A.)