The correct name for the walnut we use is walnut. In North America, this tree is agriculturally planted for walnut harvesting, while in our country, as a European walnut tree, this tree occurs only wild and isolated. Walnut is one of the noblest hardwoods of all and has therefore long been used for upscale furniture making. American walnut is characterized by a purple to dark brown color, the sapwood is lighter, white-yellowish. Walnut tends to brown with a yellowish cast when exposed to strong daylight. Therefore, it should not be exposed to direct sunlight if you do not want this discoloration.