Mohair needs to be classed (or sorted), as various types of mohair perform differently during processing and due to certain determining fleece characteristics, may require different processing systems.
Uniformity of classing is achieved when mohair is prepared for sale in accordance with industry standards and requirements.
This is achieved by ensuring optimum uniformity exists within each classed lot in relation to the physical characteristics of mohair, that each lot is correctly described, and all bales are correctly branded regarding their contents, thereby ensuring the necessary degree of confidence.
Fibre should be assesed for Finesness (Micron), Length, Kemp Levels, Style and Character, Lustre, Condition and Vegetable Matter content.
Move to mirror International Classing Standards
In March 2018 we came to realise that moving to standards that better reflect those in use in South Africa, would enable buyers a greater degree of confidence and producers a more accurate realisation of where their fibre sits on a world platform. Our classing standards booklet has been rewritten and a copy can be mailed to you by contacting the office or downloaded here.
We offer our producers in-store classing appointments.
Producers are encouraged to avail themselves of this service as it involves all facets of store classing and preparation of their clip. Valuable information and advice regarding individual clips is provided and this service is offered to AMMO clients free of charge.
Fineness is the most important characteristic to be evaluated when appraising the physical characteristics of mohair. Experienced trained classers with the necessary technical knowledge and experience can achieve accurate assessment of fibre fineness via subjective appraisal.
Subjective appraisal of relative fineness of mohair is best achieved by evaluating both softness of handle and definition of crimp/wave within the staple. The softer the handle, and the finer the crimp, the finer the fibre. Kids produce the finest fibre at their first shearing (i.e. six months of age). The fibre diameter of mohair increases as the Angora ages.
Fine Fine Kid Lines are generally 22 – 25 micron.
Fine Kid Lines are from 25 .1 – 28 micron.
Kid Lines are from 28 .1 – 30 micron.
Fine FIne Young Goat Types range from 28 .1 – 30 micron.
Fine Young Goat Types range from 31 – 32 micron.
Fine Fine Adult Lines are 32 .1 – 34 micron
Fine Adult Lines are 35 – 36 micron.
Hair Lines are 37 -42 micron
Accurate appraisal of staple length is essential. When evaluating staple length, it is the average length of all staples within a fleece that is important to be determined, not the maximum length of some staples.
In fleece types that have obviously weak tips (due to poor nutrition, harsh environmental factors, poor breeding etc. at least the top 10mm – 20mm should be disregarded when evaluating length as this weak fibre will break off during processing. Uniformity of length is as important as uniformity of micron. The more uniform the staple length is, the better the result will be regarding the performance during processing.
The length requirements for A, B, C, D and E length prefixes are described as follows:
A Length Greater than 160mm
B Length 125mm to 150mm
C Length 100mm to 125mm
D Length 75mm to 100mm
E Length 50mm to 75mm
To evaluate the average staple length of a fleece and achieve an accurate result, representative staples from the britch, flanks, neck and back areas of the fleece should be examined. A useful tool is the AMMO Length card. Download, print and laminate for best results. Hard copies can be obtained by contacting our office.
Kemp or medullated fibre content affects the spinning potential, can influence the prickle factor and dyeing ability of the processed products.
A certain percentage of kemp fibre is removed during the various processing stages, although if kemp fibre is present in significant percentages in the raw fibre, some kemp will still be present in the finished top, yarn or fabric.
As uniformity of micron and length is important, uniformity in regards to kemp content of fleeces is no exception. Levels or degrees of kemp/medullation should not vary significantly among fleeces of the same line/description. Breeders / Producers must remain ever vigilant in relation to kemp, and always select for kemp free animals and cull those with unacceptable kemp levels.
BLENDING KEMPY FLEECES THROUGH RELATIVELY KEMP FREE LINES ONLY REDUCES THE VALUE OF THE ENTIRE LINE.
Style and character does influence the processing performance of mohair fibre. Good/Super style fleeces perform better and more predictably during processing than the average and poorer style fleeces.
Style is the twist of the staple and character is the crimp. The ideal combination is an equal degree of twist and even character within a soft but firm staple structure. Too much character results in spongy/webby styled fleece, which is undesirable.
Mohair should have a bright Lustre and not be dull in appearance. Lustre is a very important characteristic in relation to processing as it accentuates the colour the manufacturers are looking for and produces a natural sheen, quality mohair is renowned for.
Grease as such, is not an undesirable characteristic as long as its presence within fleeces is light to moderate and not an excessive percentage as a proportion of the overall fleece weight.
Our traditional mohair fleece types in the past did not have sufficient condition (grease) to adequately protect the fibre from the effects of our harsh environment.
The majority of fleece types currently being produced would have combing yields between 80 – 90% with the average for * F.N.F. fleece types being about 83%.
Combing yields account for the percentage of useable fibre (clean fibre base) after the impurities such as grease, dirt, and vegetable matter have been removed.
Note: * F.N.F i.e. free or nearly free of vegetable matter, under 1%.
Vegetable fault affects both the processing potential and the type of processing system that needs to be used.
Mohair containing heavy vegetable fault (i.e. 6% and above) needs to be carbonised and fibre in the medium fault range (i.e. 3% – 6% fault) may also need carbonising (depending on the type of fault).
The carbonising process employs harsh treatments such as acid baths, baking, crushing and shaking of the fibre to remove the vegetable matter. This procedure can be a costly and time-consuming process, which results in damage to the fibre by reducing lustre and affecting the handle. Subsequently the higher the percentage of vegetable matter the less valuable the fibre is.
In relation to vegetable matter, mohair is sorted into 3 categories :
1. LIGHT FAULT – V (i.e. .1% – 3%)
2. MEDIUM FAULT – VV (i.e. 3% – 6%)
3. HEAVY, CARBONISING– CBO (i.e. 6% and greater) ( NCV – No Commercial Value )
(02) 6959 2988 F: 02 6959 3004
PO Box 16, Narrandera, NSW 2700
68 River St. Narrandera, NSW 2700