|Choosing the Right Sheep|
The value of wool is based on fiber diameter, staple length, density,
and body surface area. Fiber
diameter can be described using three different systems. First, the blood system is the oldest system.
It was started in America when the amount of sheep in the country
was low. And of these low
numbers, many were Merino. So
farmers started crossing their sheep with Merino sheep and then based
their system off of the percent Merino blood in these new sheep.
The classifications are as follows:
The next classification is the spinning count.
This relates diameter to length of yarn and weight of wool top.
These values are described as Hanks of yarn produced per pound of
clean wool. A Hank is defined
as 560 yards. The third means
of measuring fiber diameter is the micron system.
This is the most recent and most objective system.
A micron is defined as 1/25,400 of an inch.
The following chart relates some values using all three systems.
The next characteristic to determine the value of wool is staple length.
This is simply the length of the wool fiber.
The longer the staple, the higher the worth of the wool.
These values are measured in inches or sometime centimeters.
The last two components of determining the quality of wool are
included in the classification of yield, or shrink.
Yield is determined by taking 100lbs of raw wool and subtracting
shrink. Shrink includes
grease, body salts, insects, hay, and moisture.
Yields can have a wide range with the average around 46-55%.
A final characteristic of wool is crimp.
This is the "waviness" of the wool.
For fine wool, the crimp will be tight.
This tightness makes the wool more attractive and has a greater
elasticity. When the crimp is
loose, the wool is classified as coarse.
The following chart gives the fiber diameter, staple length, yield, and crimp of various wool breeds.