Mulato libre ancestors in Tlaltenango, Zac

Here's some interesting information about my great-grandmother, Emilia Gonzalez, who was from Tlaltenango. All these records are from Tlaltenango.

Clemente Gonzalez m. Anselma Figueroa (1807)
--- Jose Maria Gonzalez m. Luisa Carrillo (1837)
------ Juan Gonzalez m. Dolores Arteaga
--------- Emilia Gonzalez m. Nicanor Pineda (1914)

What I found interesting was that one of Emilia's great grandmothers (Anselma Figueroa) was categorized as an "Espanola" in her marriage record to Clemente Gonzalez. However, when I found the marriage record for Anselma Figueroa's parents: Jose Figueroa m. Juana Palacios (1777), both of her parents were called "mulatos libres."

Was it sometimes the case that a child of two mulatos libres might be considered an "Espanola" or "Espanol?" Has anyone else ever seen this?

Chris Pineda