認定高品質カシミヤ｜内モンゴル産 · グレードAファイバー
Brands throw around "Grade A cashmere" like it's a magic phrase that justifies any price tag. But most never explain what the grading system actually measures, who defines it, or why it matters to you as a buyer.
Understanding what Grade A cashmere is — and what it isn't — gives you a concrete way to evaluate whether a cashmere product is genuinely premium or just marketed as such. It comes down to two measurable properties: fibre diameter and staple length.
Cashmere is graded primarily by fibre diameter, measured in microns (one micron = one thousandth of a millimetre). The grading system used across the industry follows these thresholds:
| Grade | Fibre Diameter | Minimum Staple Length | Quality Level |
|---|---|---|---|
| Grade A | Under 15.5 microns | 34mm+ | Premium — softest, most durable |
| Grade B | 15.5–19 microns | Variable | Mid-range — noticeably coarser |
| Grade C | 19+ microns | Variable | Lower — significantly coarser, pills faster |
Fibre diameter determines softness. The finer the fibre, the more it bends when it contacts your skin, and the softer it feels. Below about 18 microns, most people cannot detect any prickle at all. At 14-15 microns, the fabric feels almost weightless against skin.
Staple length determines durability. Longer fibres produce stronger yarn because each fibre has more surface area to grip adjacent fibres in the twisted yarn structure. Short-staple cashmere (under 30mm) produces weaker yarn that pills aggressively and loses shape faster.
Grade A cashmere requires both: fine diameter AND long staple. This combination is what makes it genuinely premium.
Here's the problem: "Grade A" is not a legally regulated term in most markets. A brand can label their product "Grade A cashmere" without independent verification. There is no cashmere police.
This is why the actual micron count matters more than the grade label. A brand that tells you their cashmere measures 14.5 microns and provides third-party lab testing (such as SGS certification) to verify that claim is giving you something concrete. A brand that says "Grade A" and nothing else is giving you marketing copy.
When evaluating cashmere products, ask these questions:
Geography is not marketing — it's biology. The Alxa region of Inner Mongolia has some of the most extreme continental weather on earth: winters regularly reaching -30°C, arid desert conditions, and sparse vegetation.
Cashmere goats in this environment develop exceptionally fine, dense undercoats as an evolutionary response to the cold. The fibre they produce consistently grades at the finest end of the spectrum — typically 14 to 15.5 microns. Goats in milder climates simply don't develop the same quality undercoat because they don't need to.
China produces approximately 70% of the world's raw cashmere, but the quality varies enormously by region within the country. Not all Chinese cashmere is Grade A. The Alxa desert region specifically is where the finest fibre concentrates.
If you've only ever touched cheap cashmere from a fast-fashion retailer, you may have been underwhelmed. That's likely because you were handling Grade B or C fibre — or a cashmere blend — not Grade A.
The difference is immediately apparent to touch:
Grade A (under 15.5 microns): Feels buttery, almost liquid. No prickle whatsoever. Lightweight but noticeably warm. Drapes fluidly rather than holding rigid shape.
Grade B (15.5-19 microns): Soft but with slightly more body. You might detect a faint texture, though not prickle. Heavier hand feel. Less drape.
Grade C (19+ microns): Noticeably coarser. Some people detect a slight prickle, especially on sensitive skin like the neck. Stiffer drape. Pills more readily due to typically shorter staple length in this grade range.
The difference between Grade A and Grade C cashmere is comparable to the difference between fine silk and standard cotton. They're technically the same fibre family, but the experience of wearing them is fundamentally different.
Yes, and the reason is the staple length requirement. Grade A cashmere requires a minimum 34mm staple length. These longer fibres produce yarn with better structural integrity — each fibre wraps around its neighbours more completely, creating a tighter, stronger structure.
Short-staple fibres (common in Grade C cashmere) have more exposed fibre ends at the yarn surface. These exposed ends are what work loose with friction and form pills. More exposed ends means more pilling, faster.
A Grade A cashmere sweater with proper care can last a decade or more. A Grade C sweater typically starts showing significant pilling and shape loss within one to three seasons.
A checklist for evaluating any cashmere product claiming Grade A status:
Grade A cashmere isn't a vague quality descriptor — it's a measurable specification defined by fibre diameter (under 15.5 microns) and staple length (34mm minimum). These numbers determine how the cashmere feels, how long it lasts, and whether the price is justified. At Vionisxy, our Alxa cashmere measures 14.5 microns and every batch is SGS-certified, because we believe the grade should be verified, not just claimed.
