GRADING AND
CLASSIFICATION OF
WOOL
• Although India is among the leading countries in terms of
sheep population, the wool productivity is much lower than
the world average.
• Also, given the inadequate quality and quantity of wool
produced in India, the country imports substantial amount
of wool.
• Wool production in 42 million Kg of raw wool (2018)
• Wool is ordinarily sold by the pound on the basis of grade,
class, and quality.
• “Grade” refers to the fineness of fiber.
• “Class” refers to length of the staple or fiber.
• “Quality” refers to the freedom from foreign material and to
the “life” or character of the wool itself.
• Market value is largely determined by the fineness of the
wool.
• Wool fineness refers only to the diameter of individual wool
fiber.
• When wool is graded, the entire fleece is given a grade
that represents the average fineness and wool is placed
into grade lines with fleeces of similar fiber diameter.
• Grading is different from classing; sorting fleeces into
various lines according to fineness, length, strength,
yield, colour and style.
Wool Grading system in United States
Three systems of wool grading are used
a) American or Blood Grade System
b) The English or Spinning Count System
c) Micron System
• All the three systems are used interchangeably. But the
Micron System is used internationally and preferred by wool
buyers and manufacturers.
1. American/ Blood Grade System
• Developed in the early 1800s and originally represented the
amount of fine-wool Merino genetics (Spanish origin) present
in the native coarse-wool sheep.
• The wool grade is defined as the percentage of Merino blood
carried by the sheep that typically would produce a particular
fineness of wool.
• It includes six market grades. Grades of wool described by the
American Blood Grade System are Fine, 1/2 Blood, 3/8 Blood,
1/4 Blood, Low 1/4 Blood and Common/Braid.
American Grading Diameter Crimps Figures
FINE 20 MU C.P.I. =20
(micron units)
(Crimps per inch)
½ BLOOD 24 MU C.P.I = 14
3/8 BLOOD 27 MU C.P.I. =12
¼ BLOOD 31 MU C.P.I. =10
Low 1/4 BLOOD 34 MU C.P.I. = 8
COMMON/BRAID 40 MU C.P.I. = 4
2. The English or Spinning Count System
• Provides narrower ranges and a more exact nomenclature
than the American system.
• Uses a measurement called the “spinning count” and is based
on the number of “hanks” of yarn which could be spun from
one pound of clean wool on the equipment available at the
time the system was developed.
• Finer wools have more individual fibers per unit of weight.
Consequently, more hanks of yarn can be spun from fine
wool than coarse wool.
• One pound = 450 gm
• A hank of yarn is 560 yards in length
• In theory, one pound of clean 62s spinning count wool could
produce 62 hanks or 104,160 feet of yarn. (A hank of yarn is 560
yards in length.) Although wool is seldom spun to its maximum
count, there is a limit to the number of fibers which will hold
together in yarn.
• The English or Spinning Count system of grading wool provides a
numerical designation of fineness.
• The numerical count system divides the wool into 14 grades,
designated by a number. English or Spinning Count grades of
wool commonly used in the United States today are: 80s, 70s,
64s, 62s, 60s, 58s, 56s, 54s, 50s, 48s, 46s, 44s, 40s, and 36s.
3. The Micron System
• Increased emphasis on an exact and highly descriptive method
of describing wool grade has produced a measuring system in
which individual fibers are accurately measured.
• The unit of measure is the micron, which is one millionth of a
meter or 1/25,000 of an inch.
• Fineness is expressed as the mean fiber diameter.
• Eventually, this system became the standard for describing wool
in the United States.
Relationship between American, English and Micron System of
Grading of Wool
Type of Wool American or Blood English or Spinning Micron (range in avg.
Grade Count Grade fiber diameter)
Fine Fine Finer than 80s Under 17.70
Fine Fine 80s 17.70 - 19.14
Fine Fine 70s 19.15- 20.59
Fine Fine 64s 20.60-22.04
Medium 1/2 Blood 62s 22.05-23.49
Medium 1/2 Blood 60s 23.50-24.94
Medium 3/8 Blood 58s 24.95-26.39
Medium 3/8 Blood 56s 26.40-27.84
Medium 1/4 Blood 54s 27.85-29.29
Medium 1/4 Blood 50s 29.30-30.99
Coarse Low1/4 Blood 48s 31.00-32.69
Coarse Low1/4 Blood 46s 32.70-34.39
Coarse Common 44s 34.40-36.19
Very Coarse Braid 40s 36.20-38.09
Very Coarse Braid 36s 38.10-40.20
Very Coarse Braid Coarser than 36s Over 40.20
Grading of Indian Wools
•Wool grading in India is done by trained classer at shearing
stage. After skirting (i.e. removing objectionable parts) they
grade wool into coarse, medium and fine varieties for each
individual breed separately.
•In fact, the method of classing in the principal wool producing
countries differs considerably.
•The grading or classing of fleece is done on visual appraisal of
length, fineness (handle or feel) colour and vegetable content
as burr.
• FAO/UNDP grading
Grading of Indian wools was initiated under FAO/UNDP projects
based on wool quality, length, colour and vegetable fault
(content of vegetable matters, e.g. burr, and seed). They have
mentioned 90 types of grade.
• Indian Standard Institution (ISI) grading (IS 2900: 1979)
ISI grading is based on micron value & prescribed 120 grades which
are hardly operative
Grade Fineness range Burr Colour
A Below 34.4 LB – below 3% White
B 34.4- 37.0 MB- 3.5% Tinged White
C 37.1-40 HB- above 5% Light Yellow
D 40.1 to above - Heavy Yellow
Style Grading
•This grading system was introduced in Rajasthan which cuts the
graders to 32 only.
• It is based on the recommendation of FAO experts and is
followed by wool producing states like Punjab, Haryana, J&K,
Gujarat and Karnataka etc. incorporating some appropriate
modification in it.
Style Code No. Description
(a) Good 1 Wool with good colour, washed, skirted and vegetable
matter content of 0- 3 % with reasonable quality and
strength.
(b) Good average 2 Wool having yellow colour well skirted with vegetable
content of 0 – 3% and reasonable in quality and strength.
(c) Average 3 Wool of average washing, well skirted and vegetable content
of 3 – 6 %
(d) Inferior 4 Wool of poor washed category with vegetable content of
above 6%.
Classification of Commercial Wool
5 Categories:
• Fine wool for apparel type as Merino
✔ 18-24 microns, 64S to 80S, 2.5-12.5 cm length
• Medium wool for Coat and blanket
✔ 50S to 62S, 5-12.5 cm length, 40-60% scouring yield
• Long wool for plain cloths
✔ 44S to 50S, 65- 80% scouring yield
• Crossbred wool for worsted fabric
✔ 58S and below, 2.5-7.5 cm long
• Carpet wool <44S
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