The figures in Opuestos are made in La Union Tejalapam, a Oaxacan village that lies in a valley between the mountains of the Sierra Norte. Martín Santiago, a farmer, began carving in the late 1960s. Soon after, his brother Quirino followed him into the trade to supplement his income as well.
The figures are made from the wood of the flowering jacaranda tree. After carving the pieces are painted with natural aniline dyes. Making the pieces requires enormous skill as the artisans work with machetes on small pieces of wood. Quirino and Martín take their inspiration from the world around them. They observe their own livestock such as goats and cows; domestic animals such as cats and dogs and the wild animals they sometimes see such as deer and lynx.
Quirino and Martín carved most of the figures in Opuestos; their brother Placido and his sons Calixto and Eloy, nephew Maximino Santiago, their cousin Julio Jimenez, and Martin's son Jaime also contributed work for the book.