Lignum Vitae

Lignum vitae is a trade wood, also called guayacan or guaiacum, and in parts of Europe known as pockholz, from trees of the genus Guaiacum. This wood was once very important for applications requiring a material with its extraordinary combination of strength, toughness and density. It is also the Jamaican national flower.

The wood is obtained chiefly from Guaiacum officinale and Guaiacum sanctum, both small, slow growing trees. All species of the genus Guaiacum are now listed in Appendix II of CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) as potentially endangered species. Demand for the wood has been reduced by modern materials science, which has led to polymer, alloys and composite materials which can take lignum vitae's place.

"Lignum vitae" is Latin for "wood of life", and derives from its medicinal uses; lignum vitae resin has been used to treat a variety of medical conditions from coughs to arthritis, and chips of the wood can also be used to brew a tea. Other names for lignum vitae include palo santo (Spanish for "holy wood") and 'bastard greenheart' (not to be confused with true GreenheartChlorocardium rodiei)a popular wood in shipbuilding, cabinetry, and woodturning but a completely different timber; lignum vitae is also one of the numerous hard, dense woods loosely referred to as ironwood.

Lignum vitae is hard and durable, and is also the densest wood traded (density: 1.23 g/cm3 ); it will easily sink in water. On the Janka Scale of Hardness, which measures hardness of woods, lignum vitae ranks highest of the trade woods, with a Janka hardness of 4500 lbf (compared with African Blackwood at 2940 lbf, Hickory at 1820 lbf, red oak at 1290 lbf, Yellow Pine at 690 lbf, and Balsa at 325 lbf).

Various other hardwoods of Australasia (e.g., some species of Acacia and Eucalyptus) may also be called lignum vitae and should not be confused. The best-known is from Bulnesia arborea and Bulnesia sarmientoi (in the same subfamily as Guaiacum) and is known as Verawood or Argentine lignum vitae; it is somewhat similar in appearance and working qualities as genuine lignum vitae. In the early 2000s the Dogfish Head brewery commissioned a 10,000 gallon brewing barrel made of the latter after hearing that locals used this wood for wine production.