Terra-Cotta is both a color and a type of tile with ancient connections. Terra-Cotta means "baked earth". Popular Terra-Cotta is typically orange-ish-brown in collor but can also be brown and grey, and red, and orange with infinite variations and flashings.
Both Terra-Cotta and Saltillo are in fact usually softer than today's typical ceramic tile. Terra-Cotta and Saltillo can be either baked in a kiln or baked in the sun. Saltillo is the name of the Mexican town where the (Saltillo) product originates.
The higher the heat used in firing, the higher the density of the fired product becomes.
Both products have been severely *******ized over time.