Some sweaters look tired by the third wear. Others get better with the years until they become that sweater — the one you'd wear every day if you could. The difference is almost never the price tag: it's a combination of fibre, spinning and construction that you can learn to read in under a minute, in a shop or on a product page.
At amt. we've been making knitwear in small ateliers near Barcelona since 2016, so this subject is close to home. This is the guide we wish existed every time someone asks us "how do I know if a sweater is good?".
1. Start with the label: the fibre
There is no perfect fibre; there are fibres suited to different needs.
- Merino wool. Fine, soft — nothing like the itch of old-school wool — and thermoregulating: warm without being stuffy, wearable even between seasons. Naturally elastic, so it springs back into shape. One thing to watch: being a fine fibre, it needs good spinning — the 30-second test below will tell you.
- Wool and wool blends. Regular sheep wool is more rustic and extremely durable. Blends with cotton or cellulosic fibres soften the touch and lighten the garment.
- Cotton. Ideal if wool feels too warm or your skin is very sensitive. Less elastic than wool: look for dense knits so it doesn't sag.
- Cashmere. Wonderful and delicate at once. Beware suspiciously cheap cashmere: it's usually made from short fibres that dissolve into pills within weeks.
- Acrylic and polyester. The fibres of disposable knitwear. They don't breathe, they build static, and their pills — unlike wool's — are permanent. If the label goes past 30–40% synthetic, you know what to expect.
Quick rule: the shorter and cheaper the fibre, the worse the sweater ages. That's why two "wool" sweaters can behave in completely opposite ways.
2. The 30-second test (no expertise required)
- Hold the knit up to the light. A well-knitted sweater lets light through evenly, barely at all. Uneven "holes" and thin patches mean a loose knit that will lose its shape.
- Stretch gently and release. Does it snap back? Good sign. Does it stay stretched? Bad one.
- Check the shoulder and armhole seams. On a quality sweater they're flat, finished, with no loose threads. Linking — joining the knitted panels — is one of the most expensive operations in knitwear: where it's skipped, it shows.
- Weigh it in your hand. At equal thickness, a sweater made of noble fibre with a dense knit drapes with body. Cheap knitwear is surprisingly light and hollow.
- Run your hand against the grain. If it sheds fibre by the handful in the shop, imagine in your wardrobe.
The label tells you
almost everything.
3. Let's talk about pilling (no taboos)
Here's what almost no brand will tell you: any natural fibre can pill. Pills appear when the shorter fibres in the yarn migrate to the surface through everyday friction — your bag strap, the car seatbelt, the edge of your desk — and tangle into little balls.
What matters isn't whether they appear — it's how they behave:
- On quality wool, pills are loose fibres from the spinning process that show up mostly in the first weeks of wear, in friction zones. They come off easily with a cashmere comb or a fabric shaver, and once those loose fibres are gone, the sweater settles down and pills less and less. It's a natural settling process, not a defect.
- On a synthetic or cheap short-fibre sweater, the fibre is so strong that the pill never lets go: it stays anchored, grows, and the sweater looks worse every month.
We tell you this because it applies to us too: some of our wools, precisely because they're natural and softly spun, may form the odd pill with wear and friction. It's part of the fibre's life. Three habits keep it a non-issue:
- Let the sweater rest a day between wears: the fibre recovers and rubs less.
- Cashmere comb or fabric shaver a couple of times at the start of the season, always with the garment laid flat. Never pull pills off with your fingers — you take healthy fibre with them.
- Wash rarely, inside out, in cold water. Wool barely needs washing; airing is almost always enough.
4. Price, properly measured: cost per wear
A €90 sweater worn 40 times a year for 6 years costs €0.37 per wear. A €25 one that loses its shape in a season and gets worn 20 times costs €1.25 — more than triple, not counting the waste of binning clothes after two years. The expensive garment isn't the one that costs more on the day you buy it; it's the one you barely wear.
This calculation — cost per wear — is the best antidote to impulse buying: before you buy, ask yourself how many times you'll honestly wear it.
5. How we do it at amt.
Our knitwear — like the Galeta Jersey and Galeta Cardigan — is knitted in small family ateliers near Barcelona, with dense knit tension and materials chosen to last years, not seasons. We produce in small batches: every piece passes through hands that check it one by one. And when a natural fibre asks for a little care — a comb now and then, a cold wash — we tell you straight, because a sweater that lasts a decade is the most sustainable decision there is.
→ Discover our knitwear
→ Is your sweater a Tencel blend? Here's how to care for it: How to Care for Tencel
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