There is a distinct difference in color between the nearly white sapwood of walnut and the heartwood, which ranges in color from a deep, rich dark, almost chocolate brown to a purplish black. The wood often has a purplish cast with dark streaks. However, there is a wide variation of color, figure, and grade within the species. The grain of walnut is mostly straight and open, though some boards may have a grain pattern that is burled or curly.
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