Quebracho(Schinopsis lorentzii) grows only in the jungles of the Gran Chaco, an area along the banks of the Paraguay River. Quebracho Yellow extract comes from the common Quebracho and the wood is quite heavy and extremely hard. The name is derived from the Spanish quebrar, to break, and hacha, an axe. It is quite slow growing. Quebracho has a long history as a tanning agent and as a dye. It is most suitable for dyeing cellulose fibers, but also performs well on silks and wool.