The hardest wood in the world is Australian Buloke, registering 5,060 pounds of force on the Janka hardness scale. Certain strands of the wood species are listed as endangered by the Australian government. It is often used for making knife handles, flooring and furniture but is seldom available outside Australia.
Wood hardness is calculated using the Janka scale, which measures the force required to embed an 11.28 millimeter steel ball into wood to half the ball's diameter. The hardest wood commercially available in the United States is hickory. Hardwood species are used for furniture and flooring due to their resistance to wear and tear.