Mohair First Clip Quality
Mohair, like all fibre used in textiles, varies in quality. There are a number of characteristics which determine both the amount of yarn and the characteristics of that yarn, which can be produced from a consignment of mohair. For example, more yarn can be spun from finer lines, and the yarn will usually have a softer handle. Similarly, more yarn can be spun from longer fibre and the yarn will be stronger.
Manufacturers are concerned with both the amount and the characteristics of a yarn spun from a particular consignment. Of concern also, is the amount of effort required to do so. It is, for example, possible to spin a virtually identical yarn out of good fibre compared to burry fibre, but it takes extra combing, more time and additional cost to process the burry fibre.
The components of mohair quality are:-
Lustre and whiteness are often seen as quality factors but are largely characteristics of all mohair once scoured. Exceptions include residual staining and the presence of long medullated fibre which can occasionally effect whiteness and the perception of lustre.
Manufacturers classify mohair (and wool) according to the freedom of inferior fibre and the ease of processing.
"Spinners" describes the easiest fibre to process requiring no specialised machinery. The term is rarely used for mohair.
"Best Top-makers" describes the most desirable fibre for mohair processing by top makers.
"Average Top-makers" describes acceptable fibre for most purposes while "Inferior types" such as cots, vegetable faulted lines and very kempy mohair require extra work during processing.
"Washing types" refers to short lines used in the woollen system (as opposed to the worsted system which combs burr and short fibre from longer fibre to make strong yarns). Very short fibre goes to the noils trade.
Brokers and classers try to interpret these concepts of quality when they decide how to place individual fleeces and classed lines together to form sale lots.
Buyers may have a further decision as to which lots to place together to fill an order from a mill.
An industry standard for classing is of assistance but no two classers produce exactly the same lines and no two clips are exactly the same. Specifications therefore are only recommended objectives and some variation will always be present. The level of adherence to specification also varies with the classing. Spinners and Best Top Makers types requiring greater care and less variation from the desired specification.
The best mohair has an even fibre length with blocky staples between 13 and 16cm long. It has "Super" style, meaning a clear lock with no cross fibres and an even crimp (character) and twist (style). The twist should reverse its direction several times so the lock does not pull tight into a rope. This fibre should have a bright, lofty appearance with little, if any, kemp, burr, or stain. It should be pleasing to handle.
Lesser quality lines may be more variable in length though conforming to the general length grades of A =13-17cm, B =11-13cm and C = 7-11cm. (The lower limit for Kid is 1cm less for A & B). "Best" lines should be free of kemp, burr, and cots and stain. Blocky stapled mohair of marginal length (ie 12-13 and 10-11cm) can be placed in the A and B line, respectively. "Average" lines may have some cross fibred fleeces and varying levels of kemp. Kemp is classified as "no code", K, KK and KKK for free, slight, medium and v. kempy. Vegetable fault is classified as FNF <1%, V 1-3%, VV 3-6% & CBO >6%.
Fineness is a major quality characteristic and can be assessed using handle and crimp with finer lines having a softer handle and smaller crimp. Age is the major factor hence the terms Fine Kid, Kid, Strong Kid (or Fine Young Goat),Young Goat, Fine Hair, Hair and Strong Hair. There classes have specified micron ranges of <25um, 25-27um, 27-30um, 30-32um, 32-36um, 36-40um and >40um. Since measurement is only done after classing these are objectives for classers and Brokers to aim at, not absolute standards. However, care is needed to ensure fibre falls generally into these ranges.
First shearing fleeces are generally FK; second fleeces fall into Kid, Strong Kid (fine YG) and YG; third fleeces are mainly YG and some FH; later doe fleeces are FH and H. Old does and mature bucks produce H and SH fibre. Care is needed to remove stronger fibre from the neck before placing fleeces in classed lines.
It is of interest that super style fleeces tend to test somewhat stronger than average style mohair of the same general appearance. Super style fleeces generally have a lower diameter variation with a coefficient of variation (termed CV(D)) below about 26%, while average style mohair has a CV(D)between 26 and 32%. Super style mohair has a better handle and this may be the reason for the superior processing capacity of this fibre compared to average fibre of the same micron.
Scoured Yield is important to breeders and producers since it determines how much clean fibre an animal produces. Classers and Brokers are also concerned with grease levels since it determines how much fibre is contributed to a line by a given contributor. Classers are therefore asked to separate Light (white), Medium (grey), and Heavy (black or "wet") fleece. These lines equate to a 92%, 84% and 76% Scoured Yield.
Combing yield is of greater interest to the buyer and processor and the Schlumberger Dry Top and Noil Yield, which accounts for vegetable matter and the slightly different regain (moisture content) of top and noil, is more readily used for trading. For FNF lines (vegetable matter content below 1%) the Schlumberger Yield is about 3% lower than the Scoured Yield. Buyers usually have a preference for high Sch.Yielding fibre above about 82%.
All fleece mohair should be free of stains. Stains should be minimised by crutching and the remaining stains removed at shearing by skirting the fleece. (The skirting process should also remove all cotted and short pieces and vegetable faulted pieces). Heavy "black" stains are of little value. Lighter stains should be dry when packed.
Dark fibre (naturally pigmented fibre) is a serious fault and every effort is required to eliminate it from the industry. Some brokers offer a "Pigmented" line but this refers to white fleece with occasional pigmented fibres.
There is little doubt that superior quality mohair is desired by Buyers. However, volume and credibility are required to gain a premium for better lines. Brokers have to produce saleable lots and Buyers have to buy to fill processing orders. Some blending is necessary to achieve these goals.
Classers need to be aware of the limitations of visual classing and the overall level of production when setting up lines. Individual Brokers must set their specifications to match both production and Buyers’ requirements.
Growers and Breeders must do their part by producing the desired quality from the available animals. This means manipulation of breeding, management, nutrition, disease and parasite control, shearing management and clip preparation to maximise the quality of the whole mohair clip. Think - MOHAIR FIRST.
© 2000 Mohair Aust Ltd