Dragon's blood is a bright red resin that is obtained from different species of a number of distinct plant genera: Croton, Dracaena, Daemonorops, Calamus rotang and Pterocarpus. The red resin was used in ancient times as varnish, medicine, incense, and dye. It continues to be employed for the aforementioned purposes by some.
A great degree of confusion existed for the ancients in regard to the source and identity of dragon's blood. The resin of Dracaena species, "true" dragon's blood, and the very poisonous mineral cinnabar (mercury sulfide) were often confused by the ancient Romans, and there appears to have been a tendency to call anything that was bright red "dragon's blood". In ancient China, little or no distinction was made among the types of dragon's blood from the different species. (Both Dracaena and Daemonorops resins are still often marketed today as dragon's blood, with little or no distinction being made between the plant sources.)
Dragon's blood was used as a dye and medicine (respiratory and gastrointestinal problems) in the Mediterranean basin, and was held by early Greeks, Romans, and Arabs to have medicinal properties. Dioscorides and other early Greek writers described its medicinal uses.
Voyagers to the Canary Islands in the 15th century obtained dragon's blood as dried garnet-red drops from Dracaena draco, a tree native to the Canary Islands and Morocco. The resin is exuded from its wounded trunk or branches. When the bark or leaves are cut they secrete a reddish resin, one of the sources of the substance known as dragon's blood, used to stain wood, such as of Stradivarius violins.
Dragon's blood is also obtained by the same method from Dracaena cinnabari, which is endemic to the island of Socotra. This resin was traded to ancient Europe via the Incense Road. Socotrans use it ornamentally as well as dying wool, gluing pottery, a breath freshener and lipstick. Because of the belief that it is the blood of the dragon it is also used in ritual magic and alchemy. Dragon's blood of D. cinnabari was used as a source of varnish for 18th century Italian violin-makers. It was also used as tooth-paste in the 18th century. It is currently still used as varnish for violins and for photoengraving.
Dragon's blood resin is also produced from the rattan palms of the genus Daemonorops of the Indonesian islands and known there as jerang or djerang. It is gathered by breaking off the layer of red resin encasing the unripe fruit of the rattan. The collected resin is then rolled into solid balls before being sold.
The red latex of the Sangre de Grado tree (Croton lechleri), native to north-eastern South America, has wound-healing and antioxidant properties, and has been used for centuries by native people. The latex has medicinal properties, and is used by local peoples as a liquid bandage, applied to seal wounds, as it dries quickly to form a protective skin-like barrier. The latex also contains a number of chemicals, including taspine, that have wound-healing properties. Its use by native people has led to scientific interest, which has confirmed the sap's significant antioxidant activity.
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