Oil of sassafras varies in color from colorless to yellow and red. Its taste is pungent and aromatic, being agreeable to most persons. It has a pleasant odor resembling that of fennel, and is heavier than water, its specific gravity being 1.08 to 1.09. It is soluble in 4 to 5 parts of alcohol of 0.85 specific gravity, and consists of a mixture of various oils, among which is safrene (C_{10}H_{16}), a dextrorotatory terpene which boils between 311° and 314.6° F. By strongly cooling in a cold mixture, safrol, a crystallizing stearoptene of the composition C_{10}H_{10}O_{2}, is separated. Safrol is the chief constituent of sassafras oil. It is obtained in abundance by cooling, at a temperature of 13° F., the portion boiling between 442.4° and 455° F. It melts at 46.4° F., and at a medium temperature forms a colorless clear oil of pungent taste, characteristic odor, and specific gravity 1.104. When the crystals have been heated to above 158° F., they congeal only after remaining for weeks at a temperature below 32° F., but on being melted at 68° F., the fluid mass again congeals readily on cooling. The safrol is neutral, optically inactive, boils at 449.6° F., and is soluble in alcohol and ether. Sassafras oil is said to be frequently adulterated with oil of turpentine, which is, however, readily detected by the energetic reaction and by distilling a sample of the suspected oil. Safrol is very suitable for perfuming ordinary soaps. It has in a still higher degree than camphor oil the property of removing the disagreeable odor of some fats, while at the same time it imparts to the soaps an aromatic, refreshing odor. As a rule 8 to 11 ozs. are used for 220 lbs. of soap; but if it shall at the same time serve for removing the disagreeable odor of low quality fats, especially those extracted with bisulphide of carbon or benzine, it is advisable to take 2.2 lbs., or still better, 4.4 lbs. for 220 lbs. of soap. In this case the safrol should be added to the fat after melting and before saponification and thoroughly mixed with it by stirring. An excellent perfume for ordinary soaps is a mixture of safrol and citronella oil, it being at any rate preferable to oil of mirbane. The standard of value for safrol is its specific gravity, which should not be below 1.104 at 59° F. Specifically lighter kinds contain camphor oil and other impurities.