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
Walter Janka Walter Janka Walter Janka (born in Chemnitz 29 April 1914, died in Kleinmachnow 17 March 1994) was a German communist, political activist and writer who became a publisher. Janka is notable for having spent time incarcerated as a political prisoner under the rule of the Nazis and later imprisoned under suspicion of counter-revolutionary activities by the Supreme Court of East Germany, in both cases serving most of his sentence at Bautzen prison. Walter Janka was one of six children born to a Tool and die maker called Adalbert Janka. He attended junior school from 1920 till 1928. Between 1928 and