Sheep's wool traps air in pockets on the surface of the fibre. Alpaca fibre is semi-hollow right through its core, so air runs inside it. That single structural difference is why alpaca gives you more warmth gram for gram without the bulk — warmth you can wear inside a boot in April as easily as January.
It is also hydrophobic, absorbing only around 10-11% of its weight in moisture. Rather than soaking up sweat and holding it against your skin, it moves moisture along the fibre and out to the surface to evaporate — which is exactly what you want in a shoe with no airflow. And because alpaca contains no lanolin, there is nothing in it for sensitive skin to react against, so it suits people who have never got on with wool.
Why our socks are not 100% alpaca
Plenty of people search for a 100% alpaca sock, so it is worth being straight about why we do not make one. Pure alpaca is beautifully soft but has very little natural elasticity — a sock knitted from it alone stretches out, slips down and wears through at the heel and toe far sooner than you would accept.
Our Boot, Crew, Ankle and No-Show styles are knitted at 74% alpaca with 23% nylon and 3% spandex: enough alpaca to deliver the warmth, wicking and hand-feel, enough structure to hold shape through years of wear. Each product page states its own composition in full — we would rather show you the number than round it up. (Our discounted Everyday Alpaca pair is knitted to a different blend and lives in the outlet.)
How alpaca compares
If you are weighing alpaca against merino, cashmere or cotton, we have set the differences out honestly in alpaca vs cashmere socks and on our fibres page. The short version: merino for changeable, active days; alpaca for warmth without bulk, all-day wear and skin that dislikes wool.
