Top portion is finished with water-base urethane; bottom with oil-modified polyurethane.
Color: Heartwood is vivid reddish orange when freshly cut, darkening to reddish- or purple-brown or black over time. Sapwood is cream-colored. Very uniform in color.
Grain: Straight to interlocked; coarse texture.
Variations within species and grades: Slight variation in color.
Hardness(Janka): 1725; 34% harder than Northern red oak.
Dimensional Stability: Excellent (change coefficient .00180; 51% more stable than red oak).
Durability: Average to high durability.
Sawing/Machining: Saws well, but requires a slow feed rate; carbide tooling recommended. Machines easily, with some tearing of the interlocked grain.
Sanding: Sands satisfactorily.
Nailing: Good holding ability.
Finishing: Takes finishes well; some have found that water-based finishes hold color better. Has a tendency to bleed.
Comments: Dermatological and respiratory allergic potential.
Information is from The National Wood Flooring Association
"Wood Species Used in Wood Flooring"