African Blackwood (Mpingo)

African blackwood, known in East Africa by its Swahili name mpingo and botanically as Dalbergia melanoxylon, is a small savanna tree of the legume family. It is sometimes also known in trade as "grenadilla." Its timber is counted among the densest and hardest wood materials known; in pipe making this density is both an advantage and a source of difficulty.

The Tree and Its Wood

Mpingo grows in seasonally arid regions in a belt stretching from Senegal to Eritrea, south through Tanzania and Mozambique to the northeast of South Africa. Its height generally stays between 4 and 15 meters, and its trunk is often forked and irregular; this makes obtaining large, flawless blocks difficult. The tree takes more than sixty years to mature.

The heartwood is almost entirely black, in some pieces leaning toward dark brown or purple, with a grain pattern hard to make out with the naked eye. The surrounding sapwood, by contrast, is very thin and pale yellow; the sharp color contrast between the two layers is the material's most recognizable feature. Its measured average density runs around 1,270 kg/m³, meaning it sinks in water. Measurement tables give its Janka hardness as 3,670 lbf; this value places it at the very top rank among trees traded commercially.