Dragon's blood

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 has been in continuous use since ancient times as varnish, medicine, incense, and dye.

A great degree of confusion existed for the ancients in regard to the source and identity of dragon's blood. Some medieval encyclopedias claimed its source as the literal blood of elephants and dragons who had perished in mortal combat. The resin of Dracaena species, "true" dragon's blood, and the very poisonous mineral cinnabar (mercury sulfide) were often confused by the ancient Romans. 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; however, the resin obtained from Daemonorops has become the most commonly sold type in modern times, often in the form of large balls of resin.

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. 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.

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Wikipedia