Oil of Rose (Oleum Rosæ),
also known as attar or otto of rose. The various species of roses give different odors. The commercial Turkish, Persian, and Indian oils of rose (which latter is never exported)—which, by the way, are very generally adulterated even at their point of production—are derived mainly from Rosa damascena, and when highly diluted yield the pleasant odor of our ordinary garden roses. The rose oils having the odor of the moss rose, tea rose, or dog rose are made almost exclusively in France and in commerce do not appear pure but generally in the form of pomades or alcoholic solutions known as essences de roses.
True rose oil is yellowish or yellow, or else greenish, and varying from liquid almost to the consistence of butter. Between these extremes there are all possible gradations. A comparatively very high congealing-point is a characteristic of oil of rose. It becomes almost solid at 14 to 20° C. (57 to 68° F.). The portion separated during solidification is colorless, markedly crystalline, and, strange to say, almost odorless. Pure oil of rose smells disagreeably narcotic, only the very dilute solution shows the incomparable fragrance.
Much superior to the oils of rose which are prepared from rose leaves (either fresh or salted) are those obtained by maceration or extraction with petroleum ether. Those perfumes sold under the name of various species of rose, such as moss rose, etc., are combinations of rose oil with other aromatics.