Musk fragrances can be the best and the absolute worst. For a fairly comprehensive review of musk perfumes, you can go here, where I've written about them extensively and not just a little bit offensively. So that's your warning.
Where does the musk note in fragrance come from? Well, most commonly used in perfumery as a base note, traditionally it came from a male musk deer which is native to Asia. The male musk deer has provided this note for the use in perfumes and medicines for thousands of years. Unfortunately, in the typical process of extracting the musk glands, the deer has to meet his maker. The gland resides in the abdomen of the deer and is extracted and dried. Natural musk oil can be very expensive and may be the cause of a dramatically decreasing population of musk deer in the last century. To obtain 1 kilo of musk grains between 30 and 50 animals had to be sacrificed. In 1979, after the musk deer was listed as an endangered species, synthetic musk became much more popular. Natural musk oil has been banned in most countries and synthetic is almost exclusively used over natural musk.
So where else can they get this every popular musk oil? The Arctic Muskox, North American Muskrat and the Australian Musk Duck have also been resources that excrete a scent similar to the musk deer. Another couple sources found worldwide can be used, although not extremely successfully to create musk oil. They are the Musk Shrew and the Musk Beetle.
In 1888, creator Albert Baur combined chemicals and was successful in creating a similar natural musk oil aroma. Musk Baur became the first synthetic musk, classified under the nitro musks category. In 1894 he produced Musk Ketone, which was said to resemble natural musk fairly closely and until quite recently was among the most popular perfume ingredients. Musk Ketone along with other nitro musks such as Musk Xylol, Musk Tibetene, Musk Ambrette and Moskene all provide a warm, powdery scent, with an ambery and animalic overlay. These musks were stopped in the 1980s not only because of the hazards associated with their production, but also due to their lack of stability. The new group of musks that were created were the polycyclic musks which are sometimes referred to as white musks.
The natural substance of musk usually described as perhaps animalic or earthy or something familiar to the odor of a baby’s skin is one of the most complex aromas associated with a variety of contradictory descriptions. Most fragrances contain at least one musk component and there are many fragrances that feature musk as the prominent note.