Good musk-sacs should yield from 50 to 60 per cent. of musk. An admixture of blood is detected by the musk acquiring a putrid odor when moistened with water. The presence of pieces of metal, pebbles, resin, etc., is recognized by the naked eye or with the assistance of a magnifying glass. The microscope reveals, in pure musk, white and brownish, irregularly-formed grains, cells, oil drops, and, generally, also fungoid threads. Genuine musk burns with a white flame and leaves a gray ash, which should not amount to more than from 5 to 8 per cent.
In perfumery musk is used for soap, sachet powders, and extracts. By itself it is, however, scarcely employed, not even for the so-called musk soaps or musk extracts. It is chiefly valued by the perfumer for its property of rendering other perfumes used in combination with it more durable and bringing out their scent. For scenting soaps the musk must first be prepared. If to be used for milled soaps, it is triturated in a mortar with clear sugar, while for cold stirred soaps, weak potash lye of at the utmost 3° to 5° Bé. is poured over it. Weak lye makes the odor more pronounced, while strong lye destroys it.
_Civet_ (_zibethum_) is derived from two animals of the genus _Viverra_. The actual civet cat (_Viverra civetta, L._) lives in the hottest parts of Africa from the Guinea Coast and the Senegal to Abyssinia, where it is carefully bred for its civet. The product is also obtained from _Viverra zibetha, L._, indigenous to the Moluccas and Philippines. The civet is secreted in a cavity between the anus and the external genitals, and is scraped out with a spoon. It is semi-liquid, unctuous, yellowish, becoming brown and thicker by exposure to the air, of a bitter, disagreeable, fatty taste, and of a peculiar, urinose, disagreeable odor, resembling that of musk which becomes agreeable only when much diluted and mixed with other perfumes. When ignited it burns with a bright flame, leaving behind 3 to 4 per cent. of ash. It is insoluble in water; in spirit of wine it partially dissolves with difficulty, and with greater ease in warm ether and in chloroform. It should form a homogeneous, non-crumbling mass. According to M. Boutron Chalard, it contains free ammonia, stearin, olein, mucus, resin, a yellow coloring substance, salts, and a volatile oil, the latter giving the odor to it. In perfumery, civet is chiefly used as an addition to other perfumes in order to strengthen them and make them more constant. It is also employed for perfuming fine leather articles.