Volatility and longevity
Separate longevity, intensity, diffusion and sillage.
What you will learn
- Separate longevity, intensity, diffusion and sillage.
- Compare two observations made under similar conditions.
- Avoid promising the same duration on every skin.
Different rates of evaporation
Some molecules enter the air quickly and are perceived early; others evolve more slowly. These differences influence the fragrance’s shape and development.
Lasting power is not intensity
A material may be quiet but persistent, or strong but fleeting. Formula, dose, surface, skin and test conditions also affect lasting power.
Observe over time
Record impressions immediately, after fifteen minutes, after an hour and later. This helps distinguish a lasting character from an impressive opening.
Four terms to distinguish
Longevity is how long the fragrance remains perceptible. Intensity is the strength felt at a given moment. Diffusion describes its presence in the air. Sillage is the trail perceived as someone moves.
When the nose becomes accustomed
After repeated exposure, a familiar smell may seem less present. Step away from the sample for a while and return later. Adding fragrance whenever your perception diminishes is not a reliable measure of its longevity.
Comparing one variable at a time
Changing the number of sprays, the surface and the room at once makes the result difficult to understand. To compare two creations, keep the conditions as similar as possible. Note any differences in the test before drawing a conclusion.
Useful advice
Ask whether the person wants an intimate presence or a more noticeable trail, then offer a trial. Say “let’s observe how it evolves on you” rather than guaranteeing a duration. The aim is comfort that fits their daily life.
Useful words
Describing a sensation is not analysing a formula. Write “this reminds me of…” when offering a comparison.
Facet
One aspect of a smell: a single material may suggest lemon, green leaves and wood.
Accord
A blend of materials that creates an overall impression. It can evoke a plant without containing its extract.
Extract
A material obtained from a source through a specific process. The plant name alone is not enough: the part and method matter.
Distillation
Steam carries volatile constituents. After cooling, the watery distillate is separated from the essential oil when present.
Absolute
A fragrant extract obtained through extraction and purification, usually with solvents. It is not an essential oil.
Resin
A plant secretion distinct from needles and wood. Its extract and an essential oil distilled from foliage are not interchangeable.
Try it yourself
How to study this lesson
- Choose a fragrance and note the surface and time.
- Make a brief observation at the start, then after fifteen minutes and one hour.
- Make one final reading later without changing the test.
Apply the same fragrance to two suitable blotters, following its usual directions. Keep one at a distance and observe the other at spaced intervals. Note the time, perceived intensity and leading facets. If you smell the fragrance less, pause in neutral air and compare again: weaker perception does not prove it has disappeared.
Reveal the guidance
- Can a discreet fragrance last a long time? Yes: duration and intensity are different.
- Does a measurement on a blotter guarantee the same result on skin? No.
- Have I left a pause between my observations?
Remember
Volatility concerns the passage into the air; longevity describes how long a smell is perceptible, and intensity the strength perceived.
