Raw Wool

The traded lot is a line of baled greasy wool. Before baling, the fleece is skirted — the heavily contaminated edges are removed — and the clip is classed into lines of similar type, because a bale of mixed wool is worth less than the sum of its parts. Classing is the producer’s decision and it is consequential: the commodity that reaches the market is a constructed lot, assembled from a clip according to how the classer grouped it.

Wool fibre is a protein fibre with a scaled outer surface and a crimped structure. Those features are why it felts, why it insulates, and why it behaves as it does in spinning. But at the point of trade, wool is not assessed on any of that directly; it is assessed on measured attributes that predict how it will perform and how much clean fibre it contains.

Mean fibre diameter is the single attribute that most determines what a lot of wool is worth. Finer wool is softer against the skin, spins to finer yarns, and serves the apparel market; broader wool is stronger and coarser and goes to carpets, felts, and interior textiles. The price relationship is steep and non-linear — the premium for fineness accelerates at the fine end rather than rising evenly — which is why a small measured difference in diameter can translate into a large difference in return.

Diameter is not uniform. It varies along a staple and between staples within a fleece, so the trade reports both the mean and its variability, and the distribution matters to processors because the coarse tail of a lot influences how the fabric feels. Diameter is also not a fixed property of an animal: it responds to nutrition and season, so the same flock can produce measurably different wool from one year to the next.

Yield is the proportion of the greasy lot that survives scouring as clean fibre. It is the bridge between what is bought and what is usable, and it varies widely with the environment the sheep were run in — dusty, dry country produces heavier, lower-yielding wool than clean pasture. Because yield is measured before sale, the greasy price a buyer offers is really a clean-fibre price working backwards through the measured yield.

• Staple length — determines which processing system the wool suits and how it spins
• Staple strength — whether the staple resists breaking, and where along it a break falls
• Yield after scouring — the clean fibre recoverable from the greasy lot
• Vegetable matter — burr, seed, and plant fragments that must be removed downstream
• Colour and brightness — affects what shades the fibre can be dyed to

Staple strength deserves a note because it links directly to the animal’s year. A period of nutritional stress produces a thinner section along the fibre, and the staple tends to break there. A tender staple breaks in processing and yields shorter fibre, which is worth less — so a drought or a hard season is recorded in the wool and is paid for at sale, months later.

Vegetable matter is the contamination that matters most, because removing it costs money and damages fibre. Some is combed out mechanically; heavier burr loads may require chemical carbonising, which is harsher. A high vegetable-matter lot is discounted for a reason that is entirely downstream of the farm gate.

Greasy wool has essentially one destination: scouring. Washing the wool to remove grease, suint, and dirt produces scoured wool, the clean fibre that every subsequent textile operation actually works with. That makes scoured wool the primary product of this commodity in the strict sense — it is the intended output of the first processing step, and greasy wool is not usable as a textile fibre until it exists.

Beyond scouring the fibre moves into carding, combing, spinning, and weaving or knitting, and the wool grease recovered from the scouring effluent is refined into lanolin — a real recovered stream, but one that belongs to the scouring process and is not modelled here as a pathway of the greasy commodity.

• Apparel textiles — the destination for finer wools
• Carpets, felts, and interior textiles — the destination for broader wools
• Insulation and technical textiles

Wool is a durable, storable commodity — one of the few livestock products that does not race a clock. Pressed into dense bales it is stable for long periods provided it is kept dry, and it can be warehoused and shipped worldwide without refrigeration. That durability is why wool marketing can use auction systems and stockpiling in a way that perishable livestock products cannot.

The real storage risk is moisture. Wool is strongly hygroscopic and takes up water from the air, which both adds weight and, if the bale is genuinely wet, invites mould and fibre damage. Because moisture regain affects mass, clean wool is traded on a defined moisture basis rather than as-is weight. Contamination by foreign fibres — polypropylene from twine or packaging, or dark fibre from other animals — is the other persistent hazard, and it is disproportionately costly because a single stray fibre can show up in a dyed fabric.