This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
In commerce there appear two kinds of oil of geranium: the African or French and the East Indian. The latter is also called oil of ginger grass, and is principally employed for adulterating rose oil. The African or French oil of geranium is obtained from the leaves of geranium odoratissimum by distillation with water, a color-less, sometimes greenish or brownish oil, with an agreeable rose-like odor, extensively employed instead of the true rose-oil. on account of its being much cheaper. While the oil of geranium is also used for adulterating the oil of rose, the former itself is very frequently adulterated with the oil of ginger grass. Oil of geranium is chiefly produced in the South of France and in Turkey, where the geranium plants are largely cultivated. The brownish oil of geranium is considered the best.