In the world of luxury textiles, natural fibers like cashmere and silk are celebrated for their softness, elegance, and durability. But not all silk is created equal.
Just like cashmere sweaters vary based on the quality of the raw fibers, the quality of silk garments depends heavily on the grade of raw silk used in weaving. If you’ve ever wondered why some silk garments look radiant and last for years, while others lose shape or snag after a few wears — the answer is in the raw silk grade.
What Is “Raw Silk Grade”?
Raw silk is the unprocessed silk thread extracted directly from silkworm cocoons — the base material for weaving silk fabrics. In China, the world’s largest silk producer, raw silk is graded using the Chinese National Standard GB/T 1797-2008, which categorizes silk into 12 levels:
- From 6A (highest) down to A, then further from B to G
The higher the grade, the better the silk performs in terms of:
- Smoothness and luster
- Dye uniformity (fewer color spots or streaks)
- Fewer surface defects (knots, fuzz, or unevenness)
- Stronger durability and resistance to snagging
How Does Silk Grade Affect the Final Fabric?
✨ High-grade silk (6A-5A):
- Has a luxurious, watery shine
- Feels smoother and softer on the skin
- Shows consistent color after dyeing
- More resistant to wear, friction, and deformation
❌ Lower-grade silk (B-D):
- May show minor color inconsistencies
- Can feel rough or uneven to the touch
- Tends to snag or lose shape more easily
Even when made into the same design, garments made with higher-grade silk simply look better, feel better, and last longer.
“Cohesion Times”: Why Some Silk Snags, Others Stay Strong
One key technical indicator of raw silk quality is called Cohesion Times — a durability test that measures how well the silk fibers hold together under friction.
According to the Chinese standard:
- 6A-grade raw silk must withstand at least 100 friction cycles without splitting
- Lower grades like 2A-3A can only withstand 30–50 cycles
This explains why lower-grade silk shirts may snag after a few washes, while garments made from top-grade silk remain flawless for years.
How Is Raw Silk Graded?
Grading raw silk involves evaluating multiple technical factors. It’s not just about “how shiny it looks”. Key criteria include:
| Parameter | What It Means |
| Luster & Smoothness | Natural sheen without dullness |
| Surface Cleanliness | Minimal fuzz, specks, or residue |
| Evenness | Uniform thread thickness |
| Cohesion | How tightly the fibers bind together |
| Tensile Strength | Resistance to breakage under stress |
| Color Absorption | Even dye distribution, no blotches |
| Defect Rate | Number of visible imperfections per meter |
It’s like grading a fine wine — not just by taste, but by body, aroma, clarity, and structure.
Why Is 6A Silk So Expensive?
Top-grade raw silk, especially 6A, is rare and labor-intensive to produce. Fewer than 10% of cocoons meet this standard. Every batch must go through strict screening and testing, making it:
- More expensive (often 2–3x the cost of mid-grade silk)
- Far more durable and refined in texture
- Preferred by premium and luxury fashion houses
That buttery-soft silk blouse in your closet that still looks incredible after 30 washes? It’s probably made with 6A raw silk.
Conclusion: The Real Value of Silk Is in the Grade
When shopping for silk, many consumers look for the label “100% Mulberry Silk.” While that’s a good start, the real quality difference lies in the raw silk grade behind it.
Just as not all coffee beans or wine grapes are equal, not all Mulberry silk is created equal.
Choosing 6A-grade silk isn’t just about luxury — it’s an investment in longevity, elegance, and wearing comfort that lasts through the years.
If you’re looking to build a wardrobe of long-lasting, high-performance silk garments, raw silk grade is the secret code worth remembering.