Mohair Goes Objective - Explaining the figures
Mohair is a textile fibre similar to wool. It is produced by the Angora goat and ranges in micron from about 23 to 38um depending on age, breeding and body weight of the animals. This places it in the same range as stronger long wools but because of its smooth surface and straight form, mohair has a strong lustre and does not felt. It also has a softer handle. These characters make mohair suitable for both fine, crisp suiting materials and knitwear (made from the finer kid mohair) and brushed piled coating materials and rugs (made from mohair shorn from adult Angoras).
Since 1972 the Australian wool industry has tested wool before sale to demonstrate its quality to buyers. Fibre diameter, yield and vegetable matter content have been measured, and more recently colour and length/strength have been added to the assessment. Nearly all wool is now sold with some form of pre-sale test certificate.
In 1980, the Cudal based Mohair Broker, National Mohair Pool P/L, began testing its offering. At first buyers and mills resisted the move, arguing that mohair was too variable and the differences detected by measurement were obvious to buyers, anyway. To some extent these were the same arguments used when testing of wool was introduced. However, NMP persisted and the additional measures of colour and Diameter CV (Coefficient of Variation) were added to the pre-sale tests in 1992. Buyers are now keen to obtain the objective measurements on the sale lots.
With the revival of the mohair market in 1994, mills have been forced to become more efficient and increase processing speeds. This has increased pressure on growers and brokers to provide better specifications on sale lots. In recent times the premium for "Kid" fibre has become important. FINE KID, KID and STRONG KID types have to fall into the 24, 26, 29 micron ranges (respectively) and the only way to ensure lines meet this specification is to test the lots before sale. Stronger types, referred to as YOUNG GOAT, FINE HAIR and HAIR, usually test at 31, 34 and 37 microns.
Like wool, raw mohair contains an amount of grease and vegetable matter. Yield and VM content are routinely measured to reassure the buyers that types fall into the required specification. Mohair usually has a washing yield of between 82 and 90% and fleece lines need to average less than 1% Vegetable matter (VM). A Schlumberger Dry Top and Noil Yield accounts for the vegetable matter as well as the grease, and treats the
"regain" or moisture content a little differently. Schlumberger yields in best fleece mohair are about 3% lower than washing (or IWTO Scoured) yield and in burry fibre, are lower again because of the VM.
While mohair is a white fibre and does not usually suffer yellowing and "water" stain, a measure of whiteness is also provided. This reassures the buyer that "pooled" lines, made up of mohair from many growers with varying soil colour, will wash white. On a range from -4 to +12 fleece mohair usually obtains a whiteness test of between 0 and 3 (where 4 is usually regarded as the limit for pastel dyeing).
Diameter CV is important to spinners. If the variation is too high (above 30%) the yarn will not spin well and low CV (18-24%) puts the fibre into the "elite" category which is generally believed to enhance spinability and handle of the yarn and cloth.
National Mohair Pool has recently introduced a new service to growers. Lines of fibre (usually prepared by the grower at shearing) are tested before the fibre is "pooled". Not only does this assist the broker in placing fibre in the correct line, but it also provides a benchmark for growers. Provided growers identify lines carefully, they can get detailed information on the real quality of their flocks. Eventually this type of approach will enable the building of special low variation lines of specific micron.
To the yarn manufacturer the most important thing is the amount of yarn he can make from a give amount of raw product. In Merino wool, micron is by far the most important factor determining the yield of yarn. In stronger wools and mohair, other factors come into play. Lock length, even fibre length and the uniformity of fibre diameter becomes significant. For these stronger fibres, micron is important, but it is not the only factor governing spinability.
Objectivity is important in assisting the mills obtain the best fibre available and process it to their advantage. Predictable performance is essential to building a reputation for Australian mohair. With renewed interest in mohair, mills are now applying the lessons learned in measuring wool to mohair. Efficiency is the goal and the Australian Mohair industry is moving to accept the challenge. Objectivity will help sustain mohair the premier speciality textile fibre.
© 2000 Mohair Aust Ltd