Japanese wood oil or China wood oil, the tung oil is taken from the seed kernels of the Tung tree and is used in making wood finishes. Tung oil is considered a drying oil much as linseed, safflower, and soybean oil. Tung oil is most often used as the primary ingredient of high-quality varnishes to overcome its softness and its ability to scratch easily. It can be polymerized (heated without oxygen to about 500 degrees Fahrenheit) or mixed with varnish to improve its drying speed and hardness. A glossy sheen can also be achieved. Unfortunately, tung oil has become a generic term for a wipe-on finish. You will have to read the label in detail. Also, if it dries slowly it's probably an oil/varnish blend. If it becomes tacky in twenty minutes or less, it's probably wiping varnish.