Attar of Nishapur in Persia, much of medicine and drugs were based on herbs. Therefore, by profession he was similar to a modern-day town doctor and pharmacist. Rose oil means attar. Several musical artists have albums or songs which share the name of his most famous work, "Conference of the Birds", as well as the themes of enlightenment contained therein. Notably, jazz bassist David Holland's album, which was written as a metaphor for his own enlightenment, and Om's Conference of the Birds, which deals with extremely esoteric themes often connected with metaphors of flight, inward vision, destruction of self, and oneness with the
Essential oil are a mixture of essential oil, waxes, resins, and other lipophilic (oil-soluble) plant material. Although highly fragrant, concretes contain large quantities of non-fragrant waxes and resins. Often, another solvent, such as ethyl alcohol, is used to extract the fragrant oil from the concrete. The alcohol solution is chilled to for more than 48 hours which causes the waxes and lipids to precipitate out. The precipitates are then filtered out and the ethanol is removed from the remaining solution by evaporation, vacuum purge, or both, leaving behind the "absolute". Supercritical carbon dioxide is used as a solvent in supercritical fluid extraction.