One of the most valuable elements of a fine perfume is provided by the rose, known as the "queen of flowers". Rose perfumes were very popular with the Romans and the Greeks. Rose flowers are gathered at night since they carry fragrance before sunrise. The two main species of roses used in perfume are the Rosa centifolia, found in the South of France, and the rosa damascena (Damask Rose) located primarily in Arab countries. The damask rose is most widely grown for perfumery.
As a matter of fact, some of the most fragrant parts of plants, namely the flowers, are not suited to steam distillation. In order to prepare the odoriferous substances which impart to them their fragrant odor, other methods are employed. In such cases the volatile oils may be extracted either with volatile solvents or with fat, or they are allowed to be absorbed by fat.
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