tezontle

thumb|One of the Houses of the Mayorazgo de Guerrero showing tezontle walls with cantera accents. Tezontle () is a porous, highly oxidized, volcanic rock used extensively in construction in Mexico. It is usually reddish in color due to iron oxide. Tezontle is a well-cemented, agglomeritic and scoriaceous rock.

==Uses== ===Construction=== Tezontle can be mixed with concrete to form lightweight concrete blocks, or mixed with cement to create stucco finishes. Many colonial buildings in Mexico use the reddish cut tezontle on their facades.