It is one of the most common confusions in the bedding and sleepwear world: "silk" versus "satin." You will see both terms across online marketplaces, often at wildly different price points, and the difference matters far more than most people realise.
The Fundamental Distinction
Here is the key fact that clears up everything: silk is a fibre; satin is a weave.
Silk refers to the natural protein fibre produced by silkworms — specifically, the Bombyx mori silkworm in the case of mulberry silk. It is a material, like cotton, wool, or linen.
Satin, on the other hand, refers to a type of weave — a technique where warp threads float over multiple weft threads, creating a smooth, glossy surface. You can weave satin from any fibre: silk, polyester, nylon, or acetate.
When you see a "satin pillowcase" online for a fraction of the price of a silk one, it is almost certainly polyester satin — a plastic-based synthetic fabric woven in a satin pattern. It may look shiny, but it is fundamentally different from silk.
Natural vs. Synthetic: Why It Matters
Breathability: Silk is a natural protein fibre with an open structure that allows air to circulate. Polyester satin is plastic — it traps heat and moisture against your skin, leading to overheating and a clammy feeling during the night.
Moisture management: Silk can absorb up to 30% of its weight in moisture without feeling damp, naturally wicking perspiration away from your skin. Polyester absorbs almost nothing, leaving moisture sitting on the surface.
Hypoallergenic properties: Silk is naturally resistant to dust mites, mould, and bacteria. Polyester, being synthetic, does not share these properties and can trap allergens in its fibres.
Skincare compatibility: Silk's low absorbency means your serums and night creams stay on your skin. Polyester can absorb oils unevenly, leading to product waste and potential skin irritation.
Longevity: High-quality mulberry silk at 22 momme will last for years with proper care. Polyester satin tends to pill, lose its sheen, and degrade relatively quickly.
"If the label says 'satin' without specifying the fibre, it is almost certainly not silk. True silk products will always state the fibre, the momme weight, and the grade."
How to Spot Real Silk
Navigating the market requires a discerning eye. Here are the markers of authentic silk:
- The label: Look for "100% mulberry silk" with a specified momme weight (ideally 22 momme) and grade (6A is the highest).
- The price: Genuine silk is a premium natural material. If a "silk" pillowcase costs under 20 euros, it is almost certainly polyester satin.
- The feel: Real silk is cool to the touch and warms gradually. Polyester feels room-temperature and can feel slippery rather than smooth.
- The burn test: (For the truly curious.) Genuine silk, when a small thread is burned, smells like burning hair and leaves a crushable ash. Polyester melts into a hard plastic bead and smells like chemicals. We do not recommend performing this on finished products, but it is the definitive test.
- Certifications: Look for OEKO-TEX Standard 100 certification, which verifies the product is free from harmful substances.
Why Mulberry Silk Specifically?
Not all silk is equal. Mulberry silk — produced by Bombyx mori silkworms fed exclusively on mulberry leaves — produces the longest, most uniform fibres of any silk type. This results in a fabric that is smoother, stronger, and more luminous than wild silks (like tussah or eri silk), which tend to be coarser and less consistent.
Grade 6A mulberry silk represents the top tier of this already superior fibre: the longest threads, the most uniform colour, and the most refined texture.
The Revery and Silk Standard
Every product we create uses 100% Grade 6A mulberry silk, woven at 22 momme, and OEKO-TEX Standard 100 certified. We do not use blends, we do not use synthetics, and we do not use vague labelling.
When you buy from Revery and Silk, you know exactly what you are getting: the real thing.