Fragrance scents are made up of natural as well as synthetic ingredients. Getting scents from flowers into liquid form is a science that uses techniques like distillation (as in distilling alcohol) and enfleurage (a process that transfers aromas from flowers and other botanicals to neutral oils). Concentrating fragrances is an art as well as a science, and the essences used in fragrance production are usually super concentrated. Fragrances can actually be made up of dozens of ingredients -- sometimes as many as a hundred or more. Some of the ingredients are stabilizers, fixatives or carrier oils designed to make scents last longer once they're applied to the skin.
Fragrances contain essential oils, but not all essential oils are appropriate as personal fragrances. Think of a prepared fragrance as a rich stew of ingredients designed to smell wonderful. An essential oil is a single note scent in that stew, like lavender, lemon verbena, tea rose or cloves. Essential oils are the building blocks of fragrance, and even though you may not want to dab pine essence behind your ears for your next date, a minute amount of pine, rosemary or sandalwood essential oil mixed with flowery or citrusy oils could yield the perfect scent -- instead of leaving you smelling like a Christmas tree.
Occasionally, essential oils come pre-blended, especially for craft applications like making potpourri or candles. These blended fragrances are very concentrated though, and they're not typically used as personal fragrances.
Essential oils form the basis of most perfumes and colognes, and the perfume industry places fragrances in five basic categories: floral, woody, oriental or exotic, fernlike and fresh. Your fragrance preferences probably fall into one of these broad categories, and if you like, say, a woodsy fragrance, it's a good bet that other woodsy fragrances will appeal to you, too. You probably won't be able to pick out all the ingredients in a prepared fragrance, but knowing what fragrance category you like will make it easier for you to discuss the available options with a fragrance expert or find fragrances that have names that correspond with a particular category. Fragrance retailers are pretty savvy when naming their products; you can sometimes get an idea of the category of a scent just by its cute or colorful name.
Your favorite natural fragrance oil or other preparation will change over time, too. Temperature variations and the effects of evaporation alter some of the ingredients in prepared fragrances. Perfume experts know this and build fragrances to compensate for the way scents develop and dissipate. Most fragrances have an initial scent, a secondary scent and a base scent that begins to emerge after an hour or so. The fragrance notes you smell at the cosmetics counter may be very different from the ones you end up wearing after a couple of hours. They should still smell pleasing -- at least that's what the perfume manufacturer intends. To play it safe, test personal fragrances before you buy them by applying a sample spritz to a pulse point like your wrist and wearing it for at least an hour before deciding if you like it or not. If it still smells nice to you, you'll probably continue to like it under most circumstances. Fragrances can be unpredictable, though. They can change subtly based on factors like temperature, humidity, altitude, skin acidity and even whether or not you're a smoker or are taking medication.
By all means, find a scent you love and adopt it as your very own. Think if it as an adventure, though. Just when you think your scent is totally predictable, you'll discover it has an unexpected, subtle nuance you've never detected before. That's one of the great pleasures -- and risks -- of wearing fragrances.