In physical structure, alpaca fiber is somewhat akin to hair, being very glossy. The most valuable fleece comes from the alpaca's blanket, which is the main part of the body between the hind end and neck and above the belly.
This is a look at suri fiber. Viewing the fiber close to the skin allows you to check on the luster, since alpacas love to roll in dust. We don't wash alpacas--only their fleece after shearing!
Fiber from the neck may be as fine as the blanket in some alpacas, but generally is shorter. Although the blanket is “prime” alpaca, the neck fiber is valued by hand spinners who prepare their own fiber.
Belly and leg fiber, besides being much shorter, is less fine, but good for rugs, felting and other craft projects. I use some of the belly/leg fiber in my garden as mulch around plants!
More about suris and suri fiber
The suri alpaca evolved from the vicuña, and since the time of the Incas has been selected for its rare and unusual phenotype and fiber. Native to the Andean altiplano, some believe the suris originated in one small area of Peru, while others believe it is a recessive gene occasionally expressed in the larger alpaca population. Treasured by Inca Rulers, suri fiber was reserved exclusively for Inca Royalty, with the offense of anyone other than Royalty wearing suri fiber punishable by death.
Since the times of Inca Royalty, suri fiber has been synonymous with luxury to those lucky few who have known its qualities. With a silky soft hand and elegant luster, much of the suri fiber produced in the altiplano is sold to Italian couture houses. European processors have long recognized the 22 natural colors of huacaya alpaca, but the rare suri has been primarily only available in whites and fawns. Ultimately, though, we expect to see the same range of colors as is currently available in huacaya alpaca.
Suri fiber has some unique characteristics. It can be as fine as cashmere (17 microns being common for baby suri and tui suri), with adults ranging up to 28 microns. Due to the cellular structure of the fiber, it has a hand as soft as cashmere, but with the luster of silk. One large advantage suri has over cashmere, camel and vicuña is the longer staple length, which means items made from suri will not pill as easily.
Suri fiber is suited to both woolen and worsted processing, but shows the greatest luster when spun worsted. Knitwear made from 100 percent has a wonderful drape, but little memory (which is why I have my yarns processed with silk and/or merino).
A study funded by the Alpaca Research Foundation concludes that compared to wool of similar fineness, alpaca was shown to be much more heavily medullated (having a hollow core--a distinctive feature of alpaca), longer, and considerably stronger.
There exists much information about alpaca fiber. For example, folks traveling to South America should be aware that producers can say an item is 100% alpaca, but it may include sheep's wool or llama. It it's not very soft (or more expensive), this indicates the addition of other fibers.
It is incorrect to believe that "baby" alpaca means the produce was made from a cria--"baby" is a term indicating the grade, or micron count, of the fiber:
Alpaca fleece does not retain water, is thermal (because it is hollow) even when wet and can resist solar radiation effectively. These characteristics guarantee the animals a permanent and appropriate coat to fight against the extreme changes of temperature.This fiber offers the same protection to humans. Alpaca socks are known for their softness, warmth, and ability to wick moisture!
The Yocom-McColl lab in Denver, CO, perform tests on alpaca fiber samples they receive to determine its micron count. Reports given include the following information:
Average Fiber Diameter (AFD) is the fiber diameter in microns. Standard Deviation is a term representing an average of individual deviations (plus or minus micron values) from the mean or AFD. The smaller the Standard Deviation, the more uniform the population of fibers measured. It is the most stable of variability measures and is used in the computation of other fiber statistics such as the Coefficient of Variation (CV).
The CV is the standard deviation divided by the Average Fiber Diameter multiplied by 100 and reported as a percentage.
The percentage of fiber greater than 30 microns is of interest because it shows the coarse edge that determines the final useof the fiber. It has a relationship to the strength of the yarn processed from raw fiber and influences the "prickle" factor, the scratchy quality associated with coarser fibers.