IPE wood
IPE wood is also known as Brazilian walnut. It varies in color from reddish brown to a darker/blackish brown. This material is very durable, insect resistant. As noted on "The Wood Database" Ipe wood was used for the boardwalk along the beach of New York City's Coney Island and was said to have lasted 25 years before being replaced. It is a wood which is extremely dense and durable, not to mention a beautiful material to add to your backyard area.