Courtyard cross at the church of La Virgen de la Candelaria, Cuidad Hidalgo, Candles are lit in a small altar at the base. Disks of obsidian, which was a sacred material in local religious tradition, were set into crosses such as this, as Christian symbols were blended with locally derived styles and themes. Mexico. Spanish Colonial. mid C 16th AD. San Felipe de los Alzati, Michoacan.