Frosted Feet — Sock Materials and Warmth | frostedfeet.com
A sock label tells the micron band, the blend percentages and the fabric weight; read it together with the care rules so a warm pair survives the whole winter.
A sock label carries three numbers worth decoding: fibre diameter in microns, blend percentages, and fabric weight in gsm. Merino wool fibre is generally under 24 microns in diameter; superfine merino runs 15–18.5 microns. Below about 24 microns, wool feels smooth against skin; above that, many people find it prickly.
Blend percentages tell you what the sock actually is. Nylon or polyamide at 10–25% in the heel and toe roughly doubles abrasion life. Elastane at 2–5% keeps the cuff up without tight bands. A sock labelled 'wool' with only 20% wool behaves much more like its synthetic majority, especially in how it dries.
On narrow screens, swipe or scroll the plate sideways.
Gsm describes fabric weight, especially in the sole. A 200–400 gsm terry-loop sole adds cushioning and insulation for winter walking; a 100–150 gsm flat knit suits summer or liner use. The number is usually printed on the packaging rather than the sock itself, so keep the tag or the product page.
Care preserves warmth because warmth lives in the loft. Machine washing merino at 30 °C on a wool cycle prevents felting shrinkage; hot water and agitation make wool fibres interlock and the sock shrinks, losing both fit and loft. Synthetics tolerate warmer washes but still lose shape faster with high heat.
Skip fabric softener, which coats fibres and reduces their ability to manage moisture, and air-dry flat to protect the terry loops that trap air. Rotate two or three pairs so each dries fully between wears; a damp sock worn again loses insulation before it loses shape.
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