Mulberry silk sounds like a marketing word. It is not. It is a literal description of a diet, and that diet is the reason the fibre behaves the way it does against your skin.
One species, one food
Mulberry silk comes from Bombyx mori, a domesticated silkworm that has been farmed for thousands of years and now exists only in cultivation. It is fed exclusively on mulberry leaves, in controlled conditions, at a controlled temperature.
That control is the whole story. A wild silk moth eats whatever leaves it finds, in whatever weather it gets, and the fibre it spins reflects that variability: coarser, uneven in thickness, naturally tan or brown, and shorter in usable length. Wild silk is a genuinely good fabric with a rustic texture. It is simply a different material.
A controlled diet produces the opposite. The filament comes out fine, remarkably round in cross-section, consistent along its length, and naturally close to white, which is why it takes colour so cleanly.
One continuous thread
The property that matters most for bedding is length. A single cocoon is not made of short hairs spun together. It is one continuous filament, hundreds of metres of it, wound in a single unbroken strand.
Fabric reeled from that filament has very few fibre ends in it. Fibre ends are what work loose, surface, and tangle into pills. Fewer ends means a surface that stays smooth through years of nightly friction rather than months.
It also means the surface is genuinely smooth rather than smooth-feeling. Cotton is a staple fibre, spun from short lengths, so its surface is microscopically hairy no matter how fine the thread. Skin and hair moving across it catch, in thousands of tiny increments, all night. A continuous filament simply does not present that surface.
Round, and why that is not a trivial detail
The cross-section of a mulberry silk filament is close to circular and very fine. Wool is scaled. Cotton is a flattened, twisted ribbon. Those shapes grip. A round, fine, smooth filament does not, which is the physical reason silk feels cool and slippery rather than grabby, and the reason hair moves across it instead of being held in place while you turn over.
The same geometry is why silk sits well against the delicate skin around the eyes, where the skin is thinnest and least tolerant of being dragged.
A protein, not a plant
Silk is a protein fibre. Cotton and linen are cellulose, made by plants. Polyester is plastic, extruded from petroleum. That difference explains a lot of silk's behaviour: it is far less absorbent than cotton, so it does not draw moisture and skincare off your face and hold it; and it regulates temperature well, staying cool against skin in warm conditions without feeling clammy.
It also explains why silk needs different care. Protein fibres are damaged by the enzymes in ordinary laundry detergent, which are designed to break down protein stains and cannot tell the difference between a stain and the fabric.
What to take from this
"Mulberry" on a label is a claim about the species and the feed, and therefore about fineness, consistency and filament length. It is worth more than it sounds, because those three properties are what a pillowcase is actually made of.
The Aveloor Silk Pillowcase is 22-momme Grade 6A mulberry silk, in 17 colours.
Written by Samuel, Founder.
