The quickest way to identify what your rug is made of is to read the care label or sticker on the back, it almost always lists the fibre content (for example "100% polypropylene", "100% wool", or "viscose"). If there is no label, you can still narrow it down reliably with a few simple checks: how the pile feels, how it catches the light, what the back looks like, what the fringe is doing, and, as a last resort, a careful burn test on a single shed fibre. This guide walks through both routes so you can work out whether your rug is a hard-wearing synthetic or a delicate natural fibre, which is the single most important thing to know before anyone cleans it.
Why the fibre matters so much
A rug's fibre dictates how it must be cleaned. Synthetic rugs (polypropylene, polyester, nylon) are chemically stable plastics that tolerate moisture and a wide range of products. Natural and delicate fibres (wool, silk, cotton, viscose, jute) are the opposite, they react to pH, heat and water, and several of them are permanently damaged by the very thing people instinctively reach for: a wet cloth. Identifying the fibre first is what separates a safe clean from an expensive mistake. It also determines the price category, because delicate rugs are hand-cleaned with far more care and time. You can see how the two tiers are priced on our pricing page, and request a category directly with our rug category finder on the quote form.
Step 1: Read the label on the back
Flip the corner of the rug over and look for a stitched-in label, a printed band along one end, or a sticker. Machine-made rugs nearly always carry a fibre-content label, often required by law in the country of manufacture. What you are looking for:
- Synthetic words: polypropylene, polyethylene, PET, polyester, nylon, acrylic, "heat-set", "frieze". These are hard-wearing man-made fibres.
- Delicate words: wool, silk, cotton, viscose, rayon, "art silk", "bamboo silk", "banana silk", jute, sisal, seagrass. These are natural or semi-natural fibres that need specialist care.
- Blends: a label may read "80% wool, 20% nylon". The rule for cleaning is simple, if any delicate fibre is present, the whole rug is treated as delicate.
A genuine hand-knotted rug usually has no label, because it was woven by hand rather than finished on a production line. The absence of a label is itself a clue that you may be holding something natural and valuable, in which case treat it as delicate until proven otherwise.
Step 2: No label? Use these checks
When there is no label, these tests, taken together, will point you to the right answer. No single one is conclusive, but the pattern usually is.
Look at the back
Turn the rug over. On a genuine hand-knotted rug you will see the design clearly mirrored on the back, with thousands of individual knots, slightly irregular, because a human tied each one. On a machine-made synthetic rug the back is uniform, often with a grid-like or glued/latex backing, and the pattern is less crisp on the reverse. A printed rug (design stamped onto the surface) is always synthetic.
Feel the pile
Wool feels soft but slightly springy and dry, and it resists compression, press it and it bounces back. Synthetics often feel either slick and plasticky (polypropylene) or very soft and almost too smooth (polyester "shaggy" rugs). Silk feels cool, fine and smooth. Viscose feels soft and silky when new but mats and feels limp once it has been walked on or wetted.
Check the sheen
Hold the rug to the light. Natural silk has a deep, shifting lustre that changes colour as you move, and the sheen is even. Viscose (art silk) also shines, but with a brighter, more "white" glare and it often looks blotchy or shows shading and watermarks. A matte, flat surface usually means wool or polypropylene.
Examine the fringe
On a hand-knotted rug the fringe is part of the structure, it is the warp threads the rug is woven onto, so it is integral, not added. On most machine-made rugs the fringe is sewn or glued on afterwards. An integral fringe is a strong sign of a genuine natural-fibre rug.
The water-drop test (for suspected viscose)
If you suspect viscose, this matters more than anything else: do not experiment by dabbing the rug with water. Viscose marks permanently from a single drop. The fact that you are even worried it might be viscose is reason enough to keep all moisture away from it and treat it as the most delicate category. Read our guide on the dangers of cleaning silk and viscose rugs before you go near it with anything wet.
The burn test (last resort, one fibre only)
If you genuinely cannot tell and the rug is shedding loose fibres anyway, you can carefully burn a single strand pulled from the pile or fringe, over a sink, away from the rug. The result is diagnostic:
- Wool or silk (protein): smells of burnt hair, self-extinguishes, leaves a brittle black ash you can crush to powder.
- Cotton, viscose, jute (cellulose): smells like burning paper, burns steadily, leaves soft grey ash.
- Polypropylene, polyester, nylon (synthetic): smells chemical or sweet, melts and curls away from the flame, and leaves a hard plastic bead rather than ash.
Only ever do this with a single shed fibre, never the pile of the rug itself, and never with a rug you suspect is valuable, take it to a professional instead.
A quick reference for the common fibres
- Polypropylene (olefin): Synthetic. Cheap, hard-wearing, slightly waxy feel. Common in budget and outdoor-style rugs. Cleans easily, our standard category.
- Polyester: Synthetic. Soft, often used in plush "shaggy" rugs. Standard category.
- Nylon: Synthetic. Resilient, slightly more premium than polypropylene. Standard category.
- Wool: Natural protein fibre. Soft, springy, matte, durable. Delicate category, pH-sensitive and felts with heat.
- Silk: Natural protein fibre. Fine, cool, deep even lustre. Delicate, and high-value, hand-clean only.
- Cotton: Natural cellulose. Common in flatweaves and dhurries. Delicate, prone to browning if over-wetted.
- Viscose / art silk / bamboo silk: Semi-synthetic cellulose. Shiny but weak, mats and water-marks easily. The most delicate and unforgiving category.
- Jute / sisal / seagrass: Natural plant fibres. Rough, woven flat. Delicate, must be kept low-moisture.
Synthetic or delicate: the two categories we clean by
For cleaning and pricing, every rug falls into one of two camps:
- Synthetic / standard: The rug is made only of man-made fibres, polypropylene, polyethylene, polyester, nylon or acrylic, or a blend of just these. It is cleaned by hand at our standard rate.
- Delicate / specialist: The rug contains any natural or delicate fibre, wool, silk, cotton, viscose or jute, even in a blend. It is hand-cleaned as a specialist piece using Woolsafe-aligned, pH-appropriate chemistry, controlled moisture and dye-fastness testing.
Whatever the fibre, every rug we clean is cleaned by hand, never machine-scrubbed and never put through a factory wash line. That is why we are trusted as Persian and oriental rug specialists in Gauteng. For hand-knotted pieces specifically, read our Persian and oriental rug care guide, and for wool, our guide to cleaning wool.
Still not sure? That is normal, ask us
Fibre identification is genuinely hard, and getting it wrong is costly, so if a label is missing or you are not confident, do not guess and do not test with water. We identify the fibre, foundation and dyes during a no-obligation assessment, and we tell you honestly what category your rug falls into and what cleaning can and cannot achieve before any work begins. Send us a photo of the rug and its back via our contact page, or use the rug category finder beside the quote form to get a guide price.
Common questions
How can I tell if my rug is wool or synthetic quickly?
Feel and bounce. Wool is springy, matte and recovers when you press it; most synthetics feel either slick (polypropylene) or unusually soft and smooth (polyester). A burn test on a single shed fibre confirms it, wool smells of burnt hair and leaves crushable ash, synthetics melt into a hard bead.
Is my shiny rug silk or viscose?
Real silk has a deep, even, colour-shifting lustre and feels cool and strong. Viscose (also sold as art silk, bamboo silk or banana silk) has a brighter, glassier shine, often looks blotchy, and feels weak and mats easily. If in doubt, treat it as viscose and keep it completely dry until a professional sees it.
My rug has no label, does that mean it is valuable?
Not always, but hand-knotted rugs, which are the valuable ones, typically have no label because they were not finished on a production line. A clear knotted design on the back and an integral fringe point to a genuine hand-knotted piece, which should always be treated as delicate and cleaned by hand.
Once you know your fibre, you know your category. Enter it in the rug category finder next to our quote form for a guide price, or contact us for an honest assessment if you are unsure.