Heartwood is a golden yellow to reddish brown, sometimes with darker streaks and veins. Color tends to darken upon exposure and with age. Sapwood is a medium yellow to light gray,and is generally narrow: it can be up to 3 inches (7.5 cm) wide, and is clearly demarcated from heartwood; a narrow transition zone is sometimes present between heartwood and sapwood. African Walnut also displays a ribbon-stripe figuring on quartersawn surfaces, similar to Sapele. Grain is usually slightly interlocked, but is sometimes straight. Medium, uniform texture, with a high level of natural luster.