Five Ways to Tell Real Cashmere From Fake, at Home
Cashmere is one of the most convincingly imitated fibres in retail, and most imitations pass a casual glance in a shop mirror. None of them survive five simple checks that take under ten minutes altogether and require nothing more specialised than a lighter and a wool jumper you already own for comparison. Here is how a textile appraiser would actually check.
Start with the label, read it like a chemist
Before touching the fabric, read the composition line. In the EU and UK, garments must legally state fibre content by percentage; "100% cashmere" is a specific claim, while "cashmere blend" or a line listing cashmere alongside acrylic, nylon, or viscose is a different product entirely and, reasonably, a different price point. A jumper priced well under what raw cashmere fibre alone would cost to buy and process is very rarely 100% cashmere, regardless of what the swing tag implies through styling or photography. This single check eliminates a large share of misrepresented pieces before any physical test is needed.
The handfeel and warmth test
Genuine cashmere feels warm against the skin almost immediately, because the fibre's natural crimp traps air and the protein structure itself conducts heat away from the body slowly. Acrylic and other synthetics, by contrast, tend to feel cool or faintly clammy to the touch for the first several seconds of contact, since synthetic fibres conduct heat differently and lack cashmere's air-trapping structure. Rub a section of the fabric briskly between your fingers for about ten seconds: real cashmere will feel slightly warmer afterward, while synthetic fibre generally will not change noticeably.
The static test
Roll a section of the garment against itself, or against a wool scarf, ten or fifteen times, then hold it near loose hair or a small piece of tissue paper. Cashmere and other animal fibres generate comparatively little static under friction. Acrylic and polyester blends, in contrast, build noticeable static charge quickly, causing visible clinging or hair attraction. This test is particularly useful for blends, since even a garment that is mostly cashmere but cut with a meaningful percentage of acrylic will often show more static than a pure fibre would.
The burn test, on a hidden thread only
This test should only ever be performed on a loose thread pulled from an inside seam allowance, never on visible fabric. Hold the thread with tweezers over a heatproof surface and touch it briefly to a flame. Cashmere, like other animal fibres, burns slowly, curls rather than melts, self-extinguishes when removed from the flame, smells distinctly like burning hair, and leaves a soft, crushable dark ash. Synthetic fibre instead melts into a small hard bead, often continues burning or smoulders with dripping, and smells of burning plastic. Retailers and tailors use a version of this test routinely when fibre content is disputed, and it remains the single most conclusive check available without lab equipment.
Watch how it behaves over the first few wears
The final check requires patience rather than a tool: genuine cashmere will pill somewhat in high-friction areas such as underarms or where a bag strap sits, but the pills that form are made of fibre and lift away cleanly with a cashmere comb, leaving the surrounding knit undamaged. Poor-quality blends often pill more aggressively and unevenly across the entire surface, including low-friction areas, and the pills can be harder to remove without pulling threads. A shop-floor squeeze test cannot reveal this; only a season of ordinary wear can, which is one more reason that return policies and a trusted retailer matter as much as any single physical test.
Every OYU garment is graded and lab-tested before it is knitted — the specifics are in the fibre notes on each product page →
See also The Science of Softness: What Microns Actually Mean and Caring for Cashmere: How a Sweater Lasts Twenty Years.