For the left-wing Argentine group, see Quebracho (group). For the monetary unit, see Quebracho (money).
Quebracho is one of the common names, in Spanish, of at least three similar species of trees that grow in the Gran Chaco region of South America:
Schinopsis lorentzii (quebracho colorado santiagueno), of the family Anacardiaceae;
Schinopsis balansae (quebracho colorado chaqueno), of the same family;
Aspidosperma quebracho-blanco ("white quebracho"), of the family Apocynaceae.
These species provide tannin and a very hard, durable timber. Quebracho is sometimes used as a commercial name for the tannin derived from the trees, or their timber. The etymology of the name appears to be Spanish, derived from quiebrahacha, meaning "axe-breaker".
The tannic acid, in the form of alkalized salts, was extensively used as a deflocculant in drilling muds in 1940s-1950s, until it was replaced with lignosulfonates. Its red color gave the mixture the name red mud.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article Quebracho