What you cannot see.
Four measurements decide what a garment becomes. Not one of the four shows in a photograph.
The thickness of a fiber
Wool is measured in microns, a thousandth of a millimeter. A fine fiber bends when it meets the skin. A thick fiber resists, presses instead of giving. The skin reports that pressure. That is what makes you say “it itches”.
The threshold sits around 30 microns. Below, the fiber bends; above, it presses. Our wool does not go above 19 microns. The wool trade grades fleeces on that scale alone, long before a yarn exists.
Ultrafine, superfine, fine, medium, strong: those are the five names wool is sold under at auction.
The length of a fiber
A cotton yarn is not a continuous filament: it is a mass of short fibers twisted together. Each one has two ends, and one end always ends up migrating to the surface. It rubs, it winds around its neighbors, and the pill appears.
The shorter the fibers, the more ends there are over the same length of yarn, so the more pills there are. Ordinary cotton is 26 millimeters.
The trade draws its line at an inch and three eighths, or 34.9 millimeters: above that, the fiber is called extra-long staple. It is 3% of world production, long staple included. That is where Sea Island and Pima sit. The first grows in the Caribbean, in Barbados and Jamaica, and the whole world makes about 150 bales of it a year. The second comes from Peru and the south-western United States, where it is sold under the Supima name; that is the cotton most widely used by the houses. Our cotton does not go below 35 millimeters.
The trade counts in inches: an inch and an eighth, an inch and a quarter, an inch and three eighths. It is that last line that separates extra-long staple from the rest.
The hair that is taken out
Cashmere is the most abused word in the wardrobe, and it is still one of the most prized fibers there is.
A goat carries two coats, one over the other. Outside, a guard hair, stiff, which stops the rain. Underneath, a very fine down, which stops the cold. Cashmere is the down alone. To get it, the fleece is dehaired. Dehairing separates the fine, soft fibers from the coarse, stiff hairs known as guard hairs.
The down is 14 microns, the hair 47. That is why a badly dehaired cashmere prickles, while it is sold as the softest fiber in the world.
One goat gives 350 grams raw over the year; less than 200 are left once it is washed and dehaired.
In the United States the law puts numbers on it. To write cashmere you need a mean of 19 microns at most, a spread of no more than 24% around that mean, and no more than 3% of fibers above 30. A fiber that does not pass those thresholds has to be sold as wool.
In Europe there is no threshold at all. The regulation defines cashmere by the animal, not by the fineness. A down at 21 microns is cashmere in Europe, and is not cashmere in the United States.
A cashmere that does not move with time comes down to two measurements: the micron, which gives the thickness of a fiber, and the millimeter, which gives its length. A cashmere can be perfectly fine and perfectly short, and it is the length that decides how it holds over time. Too short, it pills in three washes, exactly like a cotton. Our cashmere does not go below 34 millimeters.
Fiber length, in millimeters. The rule is the same for both: below 28 millimeters a fiber pills, whether it comes from a goat or from a cotton plant.
The way the threads cross
Silk has its own unit, the momme, and it comes from Japan: the monme was 3.75 grams in the old Japanese system of weights. Today a momme is the weight in pounds of a piece 100 yards by 45 inches; that is 4.34 grams per square meter. A square sits between 12 and 18 mommes. The squares that count start at 14, and ours is there.
At equal fiber and equal weight, two cloths do not behave the same. In a satin, one thread passes over several others before diving back down; those long segments on the surface throw the light back, hence the sheen, but give little to hold on to, hence the slip.
In a twill, the crossings are tight and shifted by one thread at every pass: that shift is what draws the diagonal. A knot stays put on a twill and slides down on a satin, with the same silk and the same weight.
Some of our printed silks come from Liberty, in London. Each season we want to pay tribute to a craft, and we will carry on doing so when we print our own. For the first season it is Dungeness.
The fake
“Vegetable silk”. “Cactus leather”. “Eco fiber”. These are trade names, not materials. The European regulation knows only designations: polyester, polyamide, polyurethane, viscose, acrylic.
In 2025 the European Commission had 132 garments analyzed across eight countries. 49 carried a label that did not match their actual composition, or 37%.
And even when it is exact, a label stays approximate. The regulation allows margins: a garment sold as “100% cashmere” may contain 2% of something else, and a “30% cashmere” stays compliant as long as the measurement falls between 27 and 33. But an exact label is not a precise label.
Aparthés works with natural materials: lamb, calf, silk, cotton and a good many others. Synthetics we avoid, except where they are genuinely useful. On certain pieces a technical thread holds a seam or a shape; that is the usefulness in question. We write it down, and we say where it is. What we refuse is to have it dressed up as something else.
You cannot see it.
You can measure it.