Perfume is a mixture of fragrant essential oils or aroma compounds, fixatives and solvents in liquid form used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Its use has been closely tied to social status and power since the eighteenth century, when French perfumer Louis XV decreed that a royal scent should be worn by the aristocracy, bourgeois scents for the middle classes, and that only disinfectant should be worn by the poor (see image above).
The first step in the process of making perfume is mixing the desired fragrance ingredients. This can be a simple process of adding the natural or synthetic scents to a carrier like ethanol or water, which will control how concentrated and light or heavy the final product will be. It can also be a more complex process of combining oils with different levels of alcohol, which controls the concentration and how long the scent will last on your skin.
Once the scents are mixed, they are then diluted and filtered through an odour-producing molecule known as a terpene, which gives the finished product its distinctive smell. Many perfumers use a mixture of both organic and inorganic odour-producing molecules, including fatty acids that are found in certain animal secretions, such as ambergris from the sperm whale, castoreum from the beaver, civet from the musk deer, and musk from the antelope. These are combined with a variety of chemical and natural materials that act as fixatives, which reduce the evaporation rate, increase perceived odour strength, and improve stability.