Merino suits base layers, baby blankets and anything worn all day against the skin. Alpaca gives the most warmth for its weight in scarves, hats and socks. Regular sheep's wool is the hard-wearing choice for felt slippers and outer knits. The difference comes down to fibre diameter, measured in microns, and whether the fleece carries lanolin.
What is the actual difference between merino, wool and alpaca?
All three are protein fibres made of keratin, but they come from different animals and differ in thickness, surface and grease. Merino is a breed of sheep raised for very fine fleece. "Wool" on a label usually means fleece from other sheep breeds, which is coarser and springier. Alpaca comes from a South American camelid, not a sheep, and its fleece has no lanolin, the wax that sheep produce.
Those three facts, diameter, surface and grease, explain most of how each fibre behaves: how soft it feels, how warm it is, how it wears and how it should be washed.
| Fibre | Typical diameter | Lanolin | Best suited to |
|---|---|---|---|
| Merino | about 17 to 24 microns | Yes, mostly removed in scouring | Base layers, baby blankets, all-day wear against skin |
| Baby alpaca | about 22 microns or finer | None | Scarves, beanies, light warm layers |
| Regular sheep's wool | about 25 to 40 microns | Yes | Felt, slippers, outer knits, blankets that take wear |
The ranges vary by animal, grade and mill, so treat them as a guide rather than a specification.
Which fibre is softest against the skin?
Fine merino and baby alpaca are the softest of the three, because fibres under about 22 microns bend on contact instead of pressing into the skin. Regular wool, at 25 microns and above, is the one most people describe as prickly.
Softness is not only about diameter. Alpaca has flatter surface scales than sheep's wool, so it feels smooth, and it carries no lanolin, which some people react to. That is why alpaca often suits people who avoid wool, though very sensitive skin can still notice any animal fibre. The details are in does alpaca wool itch, and how to care for alpaca.
Which is warmest for its weight?
Alpaca is generally the warmest for its weight, because many alpaca fibres have a partly hollow core that traps air. A 100% baby alpaca scarf, 30 × 200 cm wraps twice around the neck and still weighs little in a coat pocket.
Merino is warm in a different way. It is not the lightest insulator, but it handles moisture well: the fibre can take up water vapour from the skin before it feels damp, which keeps a base layer comfortable across a day of walking, sitting and walking again. Regular wool is warm too, but that warmth comes with bulk. For outer layers in a Nordic winter, bulk is not a problem; for a scarf or a hat, it usually is.
Which fibre lasts longest?
Regular sheep's wool is the most hard-wearing, because its thicker, crimped fibres resist abrasion and lock together densely when felted. That is why felt slippers are made from it. Omaking, a family shoe workshop in Estonia since 1927, felts sheep's wool and lambswool into uppers that hold their shape through years of daily wear; the full range is in wool slippers for adults.
Merino and alpaca are finer and therefore more delicate at friction points. Expect some light pilling where a scarf rubs a collar or a sleeve rubs a desk. That is loose fibre working free, not a fault, and it slows once the loose ends are removed with a wool comb. Blends exist for this reason: the Alpaka alpaca socks, for example, are 44% alpaca with 36% acrylic and 20% nylon, and have a reinforced heel and toe.
Which fibre is best for babies and children?
Merino is the usual choice for babies, because it is fine, regulates temperature well and can be washed at low temperature. The Woolish baby blankets are 100% mulesing free merino, 100 by 70 cm, sized for a pram or cot. Mulesing is a practice on some merino farms in which skin is removed from around the sheep's tail; mulesing free wool comes from flocks where this is not done. The blankets are in the baby blankets collection.
For older children who find wool scratchy, a fine alpaca hat or scarf is worth trying, while still checking the label for the full composition.
How do you care for each fibre?
All three fibres prefer airing to washing, 30 °C at most, wool detergent and drying flat. The differences are small:
- Merino: often labelled for a machine wool cycle. Keep wash and rinse at the same temperature to avoid felting.
- Alpaca: hand wash or wool cycle in a laundry bag, low spin, and always dry flat, since wet alpaca stretches when hung.
- Regular wool and felt: brush off dirt when dry. Some Omaking felt slippers, such as the Halla and Nursi models, are labelled machine washable at 30 °C; check each product's label.
Between seasons, all three need the same protection from clothes moths, which feed on keratin whatever the animal. The method is in how to store wool and winter clothes for the off-season, and the Alpaka range of scarves, beanies and socks is gathered in alpaca essentials.
