How to Tell If a Silk Duvet Is Real Long-Strand Mulberry Silk
Quick answer: a quality silk duvet is filled with 100% long-strand mulberry silk, stretched into one continuous layer. The quickest tell is the stitching: a duvet quilted into a grid of small squares is usually short-strand silk, while a long-strand duvet only needs a few spot stitches. You can confirm it by opening the inspection zipper and doing a stretch or burn test.
The tell most people miss: look at the stitching
This is something you'll hear from silk duvet factories, but rarely see written down.
- Short-strand silk is loose fibre. On its own it drifts, clumps and leaves thin spots, so the duvet has to be sewn into a grid of small squares (box stitching) to hold each pocket of fill in place.
- Long-strand silk is one continuous, stretchy sheet. It holds together by itself, so it only needs a few spot stitches (tack stitches) to anchor it to the shell.
That's also why long-strand duvets feel different. With fewer seams, the silk stays soft, drapes closely over your body, and is far less likely to clump and harden over the years.
Rule of thumb: a grid of quilted squares usually means short-strand silk. A smooth surface with just a few spot stitches usually means long-strand.
See it in real products: QE Home Contessa vs. Meridian
Two duvets from QE Home, one of Canada's biggest silk duvet sellers, show this clearly. On paper they look almost identical, yet one costs about 75% more.
| Contessa | Meridian | |
|---|---|---|
| Warmth | 350 GSM | 350 GSM |
| Silk in a Queen | 65 oz (1,843 g) | 65 oz (1,843 g) |
| Fill | 100% mulberry silk floss, Grade A + B (long- and short-strand mix) | 100% Grade A long-strand mulberry silk |
| Construction | Stitch-box (quilted squares) | Ring stitch |
| Twin sale price | $269.99 | $469.99 |
Same warmth, same weight of silk and the same "100% mulberry silk" headline, so why the price gap? The difference is the fill. Contessa mixes Grade A long-strand with Grade B short-strand silk, and it's box-stitched to hold that fill in place. Meridian is all Grade A long-strand silk and doesn't need box stitching. The stitching follows the fill, just as the rule of thumb above suggests. We photographed the two side by side in a QE Home store.
Contessa (left) and Meridian (right) on display in a QE Home store. Contessa is quilted into squares. Meridian has only ring-shaped spot stitches, which look like small flowers, and no grid. The in-store cards list the fill as "100% Mulberry Silk" for Contessa and "100% Long Strand Mulberry Silk" for Meridian.
Specifications and prices are as published by QE Home on October 1, 2026 (Contessa's grade is from QE Home's product video). QE Home's own silk guide defines Grade A as long-strand and Grade B as short-strand silk. The store photos are our own. See our silk duvet price guide for the full comparison.
Long-strand vs. short-strand silk
Long-strand silk is pulled from whole cocoons and hand-stretched into a single, continuous layer. It stays in place, keeps its shape and doesn't clump. Short-strand silk is made from shorter or broken fibres. It's cheaper, but the fibres can shift, clump and form thin spots over time. In silk grading, long-strand silk is Grade A and short-strand silk is Grade B.
Mulberry vs. tussah silk
Mulberry silk comes from silkworms raised on mulberry leaves. Its fibres are fine, smooth and naturally white. Tussah, or wild silk, is coarser, uneven and usually beige or yellowish. For a duvet, mulberry silk gives a softer, more even fill.
Left: a duvet labelled only "100% Silk", with no silk type stated. Its fill is cream-yellow, fluffy and clumped, the colour and texture typical of tussah (wild) silk. Right: our 100% long-strand mulberry silk, white, translucent and stretched into one continuous web.
If a label only says "100% silk" and doesn't say mulberry, ask the seller what type of silk it is.
What is double-cocoon (dupion) silk?
A double cocoon forms when two silkworms spin one cocoon together. The fibres are tangled, so they can't be reeled into thread for fabric. Instead, they're stretched by hand into sheets of fill. That's why double-cocoon mulberry silk is the traditional choice for silk duvets.
6 checks before you buy
- Look at the stitching. A grid of small quilted squares usually means short-strand fill. A few spot stitches usually means long-strand.
- Read the label. It should say 100% mulberry silk, ideally long-strand or Grade A. "100% silk" alone doesn't tell you the type. Be wary of "silk blend", "silk-filled" or "silk touch" with no percentage; these often contain polyester.
- Open the inspection zipper. Real long-strand mulberry silk looks like a single, white, slightly shiny, web-like sheet. Short-strand or blended fill looks like loose, fluffy tufts, and tussah silk looks cream or yellowish. Check the size of the opening too: a small one only shows a patch of fill near the corner, while a larger one lets you reach in and pull the silk out to look at it.
- Do a stretch test. Pinch a little of the fill and pull gently. Long-strand silk stretches like a fine web and springs back. Short fibres simply pull apart.
- Do a burn test. Safely burn a single fibre over a sink. Silk smells like burnt hair and leaves soft ash that crumbles. Polyester melts into a hard bead and smells like plastic.
- Check the fill weight and grade. A reputable maker lists the grams of silk for each size and the grade of the fill. Higher grades mean longer, more even fibres.
The inspection zipper on a QE Home silk duvet: a small opening near the corner. Contessa and Meridian use the same one.
How we make ours
Our silk duvets are filled with 100% Grade 7A long-strand double-cocoon mulberry silk, hand-stretched into a single layer and held with hand-sewn spot stitches rather than box quilting, so the silk stays soft and drapes naturally. Every duvet has an inspection zipper, with a larger opening than the one pictured above, so you can check the silk yourself. They're made in our family's factory in Huzhou, Zhejiang. See the Canada Edition, L.A. Edition and Summer Duvet.
FAQ
Why are short-strand silk duvets quilted into squares?
Short fibres don't hold together, so they need to be sewn into small compartments to stop them drifting and clumping. Long-strand silk forms one continuous sheet and only needs a few spot stitches.
Do spot stitches make a difference to comfort?
Yes. With fewer seams, a long-strand duvet stays soft and drapes closely over your body, and it's far less likely to clump and harden over time.
How can I tell tussah silk from mulberry silk?
Look at the colour. Mulberry silk is naturally white and has a soft sheen. Tussah silk is cream to yellowish and coarser. A label that says only "100% silk" may be either, so ask.
Why are some silk duvets so much cheaper?
They often use short-strand silk, a mix of grades, tussah silk or a silk-polyester blend. These cost less to make but don't drape or last like long-strand mulberry silk. See our silk duvet price guide.
Is it safe to open the inspection zipper?
Yes. It's designed for that. Close it again afterwards and the silk stays in place.
How much silk should a duvet have?
It depends on warmth, not quality. See our fill weight guide.