THXSILK Review: Pay For Durability, Not For Magic

Silk is sold in momme, and almost nobody buying a pillowcase knows what the word means.

That is convenient for anybody selling a dearer one. This THXSILK review explains the unit first, because once you understand it the upgrade decision answers itself.

What Momme Actually Measures

One momme is 4.34 grams per square metre. It is a weight, nothing more.

Momme silk grading is not a quality scale, it is a density scale, and it works the way grams per square metre works for any other fabric.

Multiply the grade by 4.34 and you have the weight, so a 30 momme piece carries 130.2 grams of silk per square metre against 82.5 for a 19, which is 57.9% more material in the same area.

The silk itself does not change. The same 6A grade mulberry filament and the same charmeuse weave run through the range, so what you are buying with a higher number is thickness rather than a better fibre.

The Upgrade, Priced Honestly

Typical pricing across the category adds 73.2% for 57.9% more silk, and the hair and skin benefit does not move at all.

Here is the part that matters to anybody who came to silk for their hair.

The benefit comes from a smooth, low absorbency surface that lets hair slide instead of catching and does not pull moisture out of skin overnight, and those two properties belong to the fibre and the weave rather than to the weight, which means a 19 momme silk pillowcase delivers them exactly as well as a 30 does.

So the honest case for 30 momme is that it will outlast the 19. That is a real reason to spend more if you launder often and keep things for years, and it is not a reason at all if you were expecting better results.

On price per unit of weight the range is consistent, running from about $2.16 per momme at 19 up to $2.37 at 30, so the premium is modest per gram and only looks large as a headline.

The Listing Detail People Miss

Some pillowcases in this category are silk on one face and cotton on the other. Check which one you are buying.

A cotton underside version exists at 19 momme and is still sold as a silk pillowcase, which is accurate as far as the sleeping surface goes.

Flip your pillow in the night and you are on cotton, though, so anybody who turns the pillow over for a cool side should buy silk on both faces and should expect to pay for it.

The certification is worth crediting. Pieces carrying OEKO-TEX Standard 100 have been tested against a list of harmful substances, which is a checkable third party claim rather than a marketing adjective, and it is the kind of thing cheap silk on a marketplace rarely has.

Where the Reviews Disagree

Trustpilot holds 1,929 reviews at 3.8 out of 5, with 70% at five stars and 14% at one, and the company answers 80% of the negatives inside about 48 hours.

Average that spread by hand and you get 4.18 against a displayed 3.8, which means recent buyers are having a slightly worse time than the historic pool rather than a better one.

The on site widget on a single product shows 396 reviews with 1% at one star, against 14% on the independent platform, a gap of roughly fourteen times, and the reason is the familiar one that invited reviews arrive on delivery day while independent ones arrive after a problem.

1. Praise is almost entirely about how the fabric feels
2. Complaints are almost entirely about delivery and missing parcels
3. Very few people criticise the silk itself
4. A smaller group report sizing or fabric flaws on arrival

That split is useful. It says the product is the strong part and the logistics are the weak part, so the risk you are taking is about whether the parcel turns up rather than whether you will like it.

Who Should Buy

Buy if you want genuine mulberry silk with a published grade and a third party certification, you are clear that 19 momme already gives you the benefit, and you will check whether your item is silk on both sides.

Look elsewhere if you need a guaranteed delivery date, or if you are buying on a promotion, because sale items are excluded from returns and this site promotes constantly.

Final Verdict

Seven out of ten. The silk is the real thing, the momme grade and the 6A designation are published rather than hidden, OEKO-TEX Standard 100 backs it, and 70% of 1,929 Trustpilot reviewers give five stars while praising how it feels. What holds it back is delivery, which dominates the complaints, a displayed 3.8 against a raw average of 4.18 meaning recent orders go worse, and a returns policy that excludes sale items on a site that is almost always running a sale. Anyone reading a THXSILK review should buy 19 or 22 momme unless durability is the goal.

FAQs

What does momme mean?

It is a weight. One momme equals 4.34 grams per square metre, so 30 momme silk is 57.9% heavier than 19 momme.

Is higher momme better for hair?

No. The smoothness and low absorbency that help hair are the same at every weight. Higher momme buys durability.

Which grade should I buy?

Nineteen or twenty two for most people. Choose twenty five or thirty if you wash often and want it to last years.

Is it real mulberry silk?

The listings state 100% mulberry silk at 6A grade, with OEKO-TEX Standard 100 certification on the pieces that carry it.

Is the silk pillowcase silk on both sides?

On most, yes, but a cotton underside version exists, so check the specific listing.

Can I return it?

Within 30 days, unused and unwashed with tags attached, and you pay return postage. Sale items are excluded.