Silk vs Satin vs Polyester: How to Tell Real Silk
Half the confusion in silk buying comes from mixing up a fibre with a weave. Satin can be silk or polyester; charmeuse is always a silk satin; and "silk-touch" is never silk at all.
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Silk vs satin — a fibre against a weave
This is the comparison that confuses the most buyers, because the two words are not the same kind of thing. Silk is a fibre. Satin is a weave structure in which floating warp threads create a glossy face and a dull back. Silk can be woven as satin (charmeuse, duchess), and polyester can be woven as satin too — which is exactly why "satin sheets" in a hotel are usually polyester while "silk sheets" are not.
Practically: if a product is described only as "satin", you do not know the fibre. If it is described as "silk satin", you know the weave and the fibre but still not the weight — and a 12 mm silk satin behaves nothing like a 30 mm one. Ask for all three: fibre, weave, momme. Our charmeuse page lists what 12, 16, 19, 22, 25 and 30 mm are each used for, and the duchess satin page shows what happens above 22 mm.
| Silk satin | Polyester satin | |
|---|---|---|
| Hand | Dry, warm, slightly grippy when warm | Slick, cool, sometimes clammy |
| Breathability | Breathes; comfortable against skin | Traps heat; clammy at night |
| Static | Almost none | Noticeable in dry air |
| Drape | Falls with weight, holds a soft fold | Stiffer, springs back, creases stay sharp |
| Dye | Deep, slightly muted, changes with light | Bright, flat, uniform |
| Price | Multiple of polyester | Low |
Silk vs polyester: the five-minute test
No single test is conclusive, but together they settle it quickly. Keep a spare thread from any order you place — the stock page shows which qualities ship in small cuts from one metre, which is enough to test before you commit.
- Burn test (on a spare thread, never on the garment). Silk smells of burnt hair, leaves a soft crushable black bead and stops burning when the flame is removed. Polyester melts, smells chemical, and leaves a hard bead.
- Touch. Silk warms to your hand within seconds; polyester stays cool and then turns clammy.
- Stretch and rub. Rub two layers together: polyester builds static and clings, silk does not.
- Weave inspection. Silk shows slightly irregular filament thickness; polyester filament is machine-perfect and reads flat under raking light.
- Water. A drop of water spreads into silk and sits on polyester.
The word to watch is "silk-touch", "silk-feel" or "imitation silk". All three mean polyester. So does "China silk" when it appears on a cheap retail label — in the trade it means habotai, but it is also widely used to sell polyester habotai imitations.
Silk vs charmeuse
Charmeuse is silk — a satin-weave mulberry silk with a lustrous face and a matte crepe back. So the comparison is really "silk, generically" against "one specific satin-weave silk". The useful distinctions are with its neighbours: charmeuse is glossier and more fluid than crepe de chine, lighter and softer than duchess satin, and less matte than mikado.
One practical point: "charmeuse" is also applied to polyester satin in retail. If you need the real thing, specify 100% mulberry silk charmeuse, 19 momme — a seller who cannot give you the momme is unlikely to be selling mulberry silk. Our charmeuse guide covers weights and construction in detail.
Is silk stretchy?
Pure silk stretches about 15–20% before breaking and recovers poorly, so it is not a stretch fabric in the elastic sense. It feels stretchy on the bias — a bias-cut charmeuse slip will follow the body — but that is geometry, not elasticity, and the garment will grow over a day of wear.
Where real stretch is needed, we weave silk with 2–6% elastane: stretch charmeuse, stretch crepe de chine. That is the right specification for close-fitting lingerie, leggings and fitted dresses; plain silk on the bias is the right choice where you want drape without memory. See silk for lingerie and silk for sleepwear for the weights that hold a close fit.
Every family named here is on the fabric library, with momme, weight and photographs. For weight guidance by garment, see the momme chart.
Frequently Asked Questions
Is satin always silk?
No. Satin is a weave, not a fibre. Satin may be silk, polyester, nylon, acetate or a blend. If a product says only "satin", the fibre is unspecified — ask for the composition and the momme.
How can I tell if satin is real silk?
A burn test on a spare thread is the most reliable: silk smells of burnt hair and leaves a crushable black bead, polyester melts and leaves a hard bead. In the hand, silk warms quickly and does not build static; polyester stays cool and clings.
Is silk charmeuse the same as satin?
Charmeuse is a type of silk satin — satin weave, mulberry silk, glossy face and matte crepe back. "Satin" alone does not specify the fibre, so charmeuse is the more precise term.
Does silk stretch?
Pure silk stretches 15–20% before breaking and recovers poorly, so it is not elastic. Bias-cut silk feels stretchy because of the grain direction. For genuine stretch, specify 2–6% elastane in a stretch charmeuse or stretch crepe de chine.
Why is silk more expensive than polyester satin?
Silk is a agricultural fibre requiring mulberry cultivation and hand labour at reeling, and it is sold by weight — a 19 mm silk satin uses roughly five times the material of a lightweight polyester. Polyester is a petrochemical filament made at speed in continuous production.
Swatches, Weights and Wholesale Pricing
We weave 18 families of 100% mulberry silk from 3 to 70 momme, in 114 cm and 140 cm widths, with MOQ from 1 metre on stock colours. Order a swatch card, or send a garment spec and we will name the family and momme that fits it.
Email jasom@predatextile.com · WhatsApp / Skype: +86 182 9825 8162 · ready stock · wholesale