Guaiacum uses, including as lumber, for medicinal purposes, and as ornamentals. The trade of all species of "Guaiacum" is controlled under CITES Appendix II. "Guaiacum officinale" is the national flower of Jamaica, while "Guaiacum sanctum" is the national tree of the Bahamas. The genus is famous as the supplier of lignum vitae, which is the heartwood of several species in the genus. It is the fourth-hardest variety of wood as measured by the Janka hardness test, requiring a force of to embed a steel ball in diameter half that distance into the wood. The Spanish encountered guaiacum wood when they conquered
Leeb rebound hardness test a Brinell indentation on the same material is ~3 mm (hardness value ~400 HBW 10/3000), with a standard-compliant measuring time of ~15 seconds plus the time for measuring the indentation. Depending on the probe (“impact device”) and indenter (“impact body”) types that vary by geometry, size, weight, material and spring force, diverse impact devices and hardness units are distinguished, e.g.: Generally, impact device types are optimized for certain application fields. This is similar to using various indenter geometries and test loads in Rockwell (e.g. HRA, HRB, HRC), Brinell and Vickers. Leeb hardness results in HL are often converted to the