Yarn Speak: What's a Micron?
A micron is the measurement unit used to express the diameter or thickness of the individual wool fibre. One micron is one millionths of a metre. The lower the micron count the finer the wool, and therefore the higher the commercial value. Generally speaking, British wool ranges between 29 to 35 microns.
Different sheep breeds produce wool of different micron counts, although every fleece will contain a range of qualities which are graded by their average staple length and micron. Hardy highland breeds with origins in areas of poor grazing and heavy rainfall such as Welsh Mountain and Herdwick have a micron range of 30 to 35 and above. This higher micron wool is most suited for durable commercial upholstery and carpets, which need to be hardwearing.
Some of the finest wool that Britain produces comes from the fleece of the Bluefaced Leicester, which has a subtle sheen, and a soft, sumptuous hand-feel, due to its 26 to 27 micron fibre. This is a highly valuable wool which adds a distinctive cashmere-like luxury softness to handknit yarns.
