Alpaca vs Silk

Alpaca is warmer, more durable and more elastic. Silk is softer and more lustrous.

AlpacaSilk
Typical diameter18–32 µm10–13 µm
SourceAlpacaSilkworm cocoons
LanolinNoNo
Warmth★★★★★★★
Softness★★★★★★★★★
Durability★★★★★★★
Luster★★★★★★★★
Elasticity★★★★★
Price$$$$$

Bottom line

Warm for its weight, lanolin-free, silky hand; less elastic than wool.

Lustrous protein filament; often blended with alpaca.

Choose alpaca for warm, drapey, lanolin-free garments; choose silk if you value softer and more lustrous. Blends often give the best of both.

Silk is a natural protein fiber, some forms of which can be woven or knitted into textiles. The protein fiber of silk is composed mainly of fibroin (75-80%) and a smaller coating of sericin (20-25%). It is most commonly produced from the cocoons of certain insect larvae. The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori, which are reared in captivity (sericulture).From Wikipedia — “Silk”, licensed under CC BY-SA 4.0.

FAQ

Is alpaca better than silk?
Alpaca is warmer, more durable and more elastic. Silk is softer and more lustrous. Warm for its weight, lanolin-free, silky hand; less elastic than wool. Lustrous protein filament; often blended with alpaca.
Is alpaca warmer than silk?
Yes, alpaca is generally warmer for its weight.
Is alpaca softer than silk?
It depends on the grade: fine alpaca (18–22 µm) is very soft, while silk typically measures 10–13 µm.