Mulberry silk is silk from the domesticated Bombyx mori silkworm, raised on a diet of mulberry leaves, and it produces the longest, smoothest and most uniform silk filament. "Regular silk" is not one thing: a label reading 100% silk can mean mulberry, a wild silk like tussah, or spun silk made from shorter fibers. So all mulberry silk is silk, but not all silk is mulberry, and for anything that touches your face every night, that difference is one you can feel.
Here is how the main types of silk differ, what the grade letters mean (and do not mean), and where "organic silk" fits in, since it is not a separate kind of silk at all.
What makes mulberry silk different
Bombyx mori has been domesticated for thousands of years. It no longer exists in the wild, and the moths cannot fly. The caterpillars are fed mulberry leaves, and each one spins a cocoon from a single continuous filament that can run hundreds of meters long.
When those cocoons are unwound (reeled) intact, you get long, fine, even strands. That is the whole secret. Long strands mean fewer fiber ends poking out of the fabric surface. Even strands mean a consistent weave. Together they give mulberry silk its smooth hand, its even sheen and its bright natural white, which also takes dye evenly.
Cultivated mulberry silk is what nearly every silk pillowcase is made from, and it is what we use. If you want to know what the fiber itself is made of, I wrote about the amino acids in silk.
Wild silks: tussah, eri and muga
Wild silks come from other moth species, some farmed semi-wild, some gathered. They are beautiful. They are also different.
Tussah silk
Tussah comes from Antheraea moths that feed on oak and other leaves. The fiber is flatter, coarser and less uniform than mulberry, with a natural honey to golden color that is hard to bleach to a true white. It has a lovely, slightly dry texture and a softer glow. You will see it in textured suiting, shantung style fabrics and yarn for knitting and spinning.
Eri silk
Eri comes from a moth that feeds on castor leaves. Its cocoon has an open end, so it cannot be reeled into one long filament. Instead, it is spun like wool or cotton. The result is warm, matte and a little woolly. Because the moth can leave the cocoon before processing, eri is often sold as "peace silk".
Muga silk
Muga is a golden wild silk from Assam in northeast India, prized for its natural shine and durability in traditional textiles. It is rare and regionally specific, and you are unlikely to find it in bedding.
Spun silk and silk noil
Not every silk fiber comes from a perfectly reeled cocoon. Broken filaments, the outer and inner layers of cocoons and pierced cocoons still hold good silk, just in shorter lengths. Those fibers are combed and spun into yarn, which is called spun silk. It is softer and less lustrous than reeled filament silk, and more of the fiber ends sit at the surface.
Silk noil (sometimes mislabeled "raw silk") is made from the shortest leftover fibers. It is nubby, matte and breathable, with a texture closer to linen or cotton. It makes wonderful relaxed summer clothing. It is not what you want against your face if a smooth, low friction surface is the point.
Mulberry silk vs other silks at a glance
| Type | Source | Fiber | Look and feel | Common uses |
|---|---|---|---|---|
| Mulberry (reeled) | Cultivated Bombyx mori, mulberry leaves | Long, fine, uniform filament | Smooth, even sheen, bright white | Pillowcases, charmeuse, lingerie, fine scarves |
| Tussah | Wild or semi-wild Antheraea moths | Flatter, coarser, less uniform | Honey to gold, softer glow, slightly dry | Shantung style fabrics, suiting, yarn |
| Eri | Moth fed on castor leaves | Spun, not reeled | Matte, warm, woolly | Shawls, knitwear, "peace silk" |
| Muga | Wild silk moth native to Assam | Reeled, coarser than mulberry | Natural gold shine | Traditional Assamese textiles |
| Spun silk | Short and broken fibers | Combed and spun | Soft, lower luster | Knits, mixed fiber fabrics, budget fabrics |
| Silk noil | Shortest leftover fibers | Short, nubby | Matte, textured, linen-like | Casual clothing |
Is 100% mulberry silk the same as 100% silk?
Not necessarily. "100% silk" tells you the fiber content is silk and nothing else. It does not tell you the species, whether the silk is reeled or spun, or how good the filament is. "100% mulberry silk" narrows it down to Bombyx mori. Neither phrase tells you the weight (momme) or the weave, so read those next. My guide to telling real silk from fake silk covers the tests you can do at home.
What 6A actually means
Raw silk filament is commonly graded on a letter scale, with A the highest letter, followed by B and C. Within the A range, numbers add detail, and 6A sits at the top: the longest, most even filament with the fewest defects.
Here is the honest caveat. Silk grading is an industry convention, not a single regulated standard with one independent body checking every claim. Suppliers generally mean the same thing by 6A, but there is no public database where you can look a grade up the way you can a certificate. Treat grade as a meaningful signal from a supplier you trust, and put more weight on things you can verify: momme, weave and certificates.
For context, most well known brands describe their pillowcases as 6A mulberry, and some do not state a grade on their product pages at all. Ours is Grade 6A, 100% mulberry, at 25 momme. I explain why that weight matters in why we chose a 25 momme silk pillowcase.
Organic silk vs mulberry silk
This one trips people up. "Organic silk" is not a different species. It means the sericulture (the mulberry farming and silkworm rearing) and the processing are certified to an organic standard, most commonly GOTS. The mulberry trees are grown without synthetic pesticides or fertilizers, and each company in the chain has to be certified.
So organic silk and mulberry silk are not opposites. Certified organic mulberry silk exists. When a brand says its silk is organic, ask for a GOTS license number you can look up yourself. The question is not "organic or mulberry" but "mulberry, and certified how?" If certifications are your deciding factor, read GOTS vs OEKO-TEX.
Why I care: after CLL treatment I developed MCAS, and I need to know exactly what touches my skin. That is my experience, not a claim about what silk does for anyone's health. If you are managing a condition, check with your care team.
Who mulberry silk is for, and who it isn't
Choose reeled mulberry silk if you want the smoothest possible surface against your face and hair, an even sheen and a fabric that stays consistent wash after wash. For pillowcases, eye masks and scrunchies, it is the standard for a reason.
Choose tussah, eri or noil if you want texture, a matte finish, a natural golden color or a lower price for clothing or home decor. They are real silk with their own character, and they are often more affordable. Eri, as peace silk, may also suit you if how the cocoon is harvested matters to you.
Skip the label hunting if the product is labeled "satin" with no fiber content. That is a weave, usually polyester, not a type of silk.
Our Douceur Doublure™ is Performance Luxury Silk™: two layers of 25 momme, Grade 6A, 100% mulberry silk charmeuse, certified by our manufacturer, with 330 hand-numbered pieces that will not be restocked. Because we all deserve to know exactly what we are sleeping on. (And what species of caterpillar made it. Apparently.)
25 momme, Grade 6A, 100% mulberry. 330 numbered pieces, never restocked.
Frequently Asked Questions
Is 100% mulberry silk the same as 100% silk?
Not exactly. 100% silk means the fabric is made only of silk, but that silk could be mulberry, a wild silk such as tussah, or spun silk from shorter fibers. 100% mulberry silk tells you it comes from the cultivated Bombyx mori silkworm, which produces the longest and most uniform filament. Neither label tells you the momme weight or weave, so check those too.
What is tussah silk?
Tussah is a wild or semi-wild silk from Antheraea moths that feed on oak and other leaves rather than mulberry. Its fiber is flatter, coarser and less uniform than mulberry silk, with a natural honey to golden color that is difficult to bleach white. It has a softer glow and a slightly dry texture, and it is used in shantung style fabrics, suiting and yarn.
Is organic silk better than mulberry silk?
They are not competing categories. Organic silk means the sericulture and processing are certified to an organic standard, usually GOTS, including mulberry trees grown without synthetic pesticides or fertilizers. Most organic silk is mulberry silk. So the useful question is whether a mulberry silk carries a certification you can verify, such as GOTS or OEKO-TEX, and who holds that certificate.
What does 6A mean in mulberry silk?
6A is the top of the A grade scale commonly used for raw silk filament, describing the longest, most even fiber with the fewest defects. Grades run from A down through B and C. Grading is an industry convention rather than a single regulated standard, and there is no public database to look a grade up, so weigh it alongside momme, weave and certificates you can verify.
Is mulberry silk real silk?
Yes. Mulberry silk is real silk, and it is the most widely produced type in the world. It comes from the cocoons of Bombyx mori silkworms raised on mulberry leaves. The long filament from each cocoon is reeled into fine, even threads, which is why mulberry silk feels smooth and has an even sheen. Most silk pillowcases are made from mulberry silk.
What is the difference between spun silk and mulberry silk?
Spun silk describes how the yarn is made, not the species. Spun silk uses shorter fibers from broken filaments or pierced cocoons, combed and spun like cotton, so it is softer but less lustrous, with more fiber ends at the surface. Reeled mulberry silk uses the long continuous filament unwound from an intact cocoon, giving a smoother, more even fabric.
