Tung oil comes from the nuts of the tung tree (Vernicia fordii). It is hard to find pure tung oil today, like others say, purchase some from the wood working stores or suppliers that say it is genuine tung oil and not some product made to act like tung oil. This stuff produces a very nice finish if you have the genuine product. I mix it with linseed oil for my stock work. both need to be "boiled".