fiber types (mixed or not?) fiber length(s) crimp pattern(s) luster (or lack thereof ) Fiber types

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1 A basic consideration of Wool types American Karakul Things to consider in detail when first making the acquaintance of a new wool include: fiber types (mixed or not?) fiber length(s) crimp pattern(s) luster (or lack thereof ) fiber fineness or strength (fiber diameters) color(s) W 2015 Deborah Robson, all rights reserved. All photos not otherwise credited are by Deborah Robson. wool (fine) wool (long, strong, & lustrous) Merino American Wensleydale Fiber types A fleece can contain three types of fibers, sometimes in combination. These are wool; hair; and kemp. Wool comes in several varieties, from fine to coarse, and with varying amounts of crimp, luster, and other qualities. Hair tends to be slicker and coarser than the associated wool coat, although it, too, varies. Kemp is short, brittle, and stiff. hair wool Hebridean kemp hair wool South Welsh Mountain 4 inches / 10 cm by Deborah Robson 1

2 Clues from the shapes of locks If your wool has not been processed and sample locks can be identified, their shapes can be informative. Short, blocky staples tend to be associated with fine or medium wools. Long, sinuous staples tend to be sturdy, lustrous longwools. Because the breeds that produce this type of wool grow long fleeces, they are often shorn twice a year (likely the case with the sample shown here). but most often signify double-coated wools that contain both wool and hair (and possibly kemp). The coats can be spun together or, in some breeds, may be easy to separate into two types of fibers and spun into dramatically different yarns. Triangular staples can vary in length from very short to quite long, 4 inches / 10 cm weather side (tip) Rectangular with blunt tips Sinuous Triangular with wide bases and pointed tips Cormo (with jacket off) Border Leicester Icelandic sheep side (butt) 2

3 Fiber lengths Even when you don t have access to the fleece and its staples, you can easily evaluate other qualities, beginning with fiber length. Workable fiber lengths can range from 1 inch or perhaps less ( 2.5 cm) to 12 inches or occasionally more ( 30 cm). Each type of fiber has a characteristic range of fiber lengths, but the actual length of the wool in your hands is determined by the amount of time that passes between shearings. While most sheep are shorn once a year, so that the fiber length represents a full year s growth, some sheep are shorn twice a year, for any of several reasons: because they grow so much wool that it is easier to handle at a half-year s length; because of seasonal variation in husbandry practices that make, say, the fall shearing cleaner, sounder, and thus more valuable than the spring shearing; or simply for convenient management of the flock (say, a good shearer will be in the area). Fiber length determines some of what can be done successfully with wool. A very short fiber cannot be spun directly into a bulky yarn that will wear well. In order to be adequately secured by the twist, short fibers need to be made into fine yarns, and if a bulky yarn is the goal it will need to be spun into fine singles and then plied to obtain the desired weight. Very long fibers can be difficult (but not impossible!) to spin, but work splendidly as locks inlaid into weaving sheds, or caught in knitted stitches, or used as decorative inclusions in yarns spun from fibers of more normal length. No matter whether you make or buy your yarn, learning to handle fibers with different characteristics will give you the ability to create exactly the type of textile that you want. The optimal length for handspinning is likely in the range of 3 to 4 inches (7.5 to 10 cm). That s a good place to start. However, the ability to spin shorter and longer fibers greatly increases what you can accomplish. 4 inches / 10 cm Charollais (some are much longer) Dorset Down Scottish Blackface 3

4 Crimp patterns Crimp is one of the most complex (and interesting, and useful) aspects of wool structure. Crimp provides a lot of clues about how a wool will behave. Through history, some theorists and researchers have proposed that crimp patterns offer more solid information than they do-for example, have postulated that there is a direct correlation between crimp frequency and fiber diameter, and then that there is a direct relationship between fiber diameter and softness but later research has shown that these relationships are approximate and not absolute, and that wool is a lot more intriguingly complex than the original theories gave it credit for being. As a general principle, though, finer fibers have higher-frequency crimp patterns than coarser fibers. Crimp also has a lot to do with the compressibility, elasticity, and loft of yarns spun from a given wool. Qualities of crimp Frequency: How many bumps are in a given length of fiber? Amplitude: How deep are the bumps? 4 inches / 10 cm Leicester Longwool Devon & Cornwall Longwool All of the locks in all of these pages are reproduced at the same scale. The samples here show some locks with many crimp waves to the inch and some with few. In some the crimp is organized in the lock and in some it is disorganized. Corriedale Sometimes it s just a wave. Suffolk Another thing to look for is whether the crimp is evenly distributed along the length of the fibers. These clues can help you analyze locks for similarity microns, most microns microns, most microns 4

5 Organized or disorganized: Is the crimp organized in the staple or individual fiber? Evenness: Is the crimp evenly distributed from the tip to the butt of the staple or individual fiber? Crimp in a group of fibers Crimp in individual fibers In both instances, organized is on the left and disorganized is on the right. Luster refers to the light-reflecting ability of a fiber. It affects the way color is perceived. Luster (or lack thereof) Luster refers to a fiber s shiny appearance. Wool fibers are complex physical and chemical structures. The outside of every individual strand is covered with tiny scales that overlap, with their bases toward the butt of the fiber and their edges toward its tip. Each type of wool has a typical scale pattern, and the types differ from each other in the size, shape, overlap area, edge definition, and other qualities. Lustrous wools have large scales that reflect light. The Leicester Longwool lock at the far left on the opposite page demonstrates that quality exquisitely. Lustrous fibers show off their color well, whether that color is natural or dyed. Damage to the scales, through exposure to excessive heat, acid, or other forces, can reduce luster. Less dramatically obvious luster can show up in some surprising places, however. Worsted preparation and spinning techniques (where the fibers are kept in a parallel arrangement as much as one can) make the most of luster. California Red Bluefaced Leicester Romeldale Cormo microns, most microns microns microns 5

6 Fineness or strength (fiber diameter) In most cases, fine wools win points for softness and large-diameter fibers are more durable. Fineness or coarseness is the greatest determinant of value in the global wool market, with fine wools like Merinos demanding premium payments in the twenty-first century. For centuries before the introduction of Merinos, strong and shiny fleeces from sheep like Cotswolds dominated the European wool trade. Fine wools are the best used for fabrics that will be in close contact with a person s skin. As a trade-off, these textiles will not be exceptionally durable, although their sturdiness can be maximized through choices of spinning techniques. For cloth that needs to be durable, the coarser or stronger wools are better choices. The schematic here shows relative differences in size between fibers istock.com / lightshows of different micron (micrometre) counts, the micron being the way fiber diameters are measured in today s laboratories. Until relatively recently, wool grades, which closely relate to fineness, were determined subjectively by experienced evaluators. The historic and contemporary Cotswold Gary Radler Photography / Stocksy United grading systems are summarized at the top of the opposite page,. The subjective, or old-style, systems are at the top and the objective, or more recent, systems are at the bottom. Hand evaluation still has distinct value. Merino 5 18 μ 20 μ 25 μ 30 μ 40 μ 70 μ 100 μ 5 μ = tips of New Zealand possum fibers 20 to 40 μ = most wool fibers 18 μ = cashmere is at least this fine less than or equal to 30 μ = industrial comfort factor 70 μ = some human hairs μ = micron, or one millionth of a meter 100 μ = some kemp fibers 6

7 Ways of Thinking about Fiber Diameters Subjective Objective { { General descriptions Blood system Bradford counts Fine Fine Medium 1/2 blood 3/8 blood 1/4 blood Coarse or Strong Low 1/4 Common Very coarse or Very strong Finer than 80s 80s 70s 64s 62s 60s 58s 56s 54s 50s 48s 46s 44s 40s 36s Coarser than 36s Microns (μm) Finer than 80s 80s 70s 64s 62s 60s 58s 56s 54s 50s 48s 46s 44s 40s 36s Coarser than 36s { USDA wool < grades Average micron count Standard deviation SD 3.59 SD 4.09 SD 4.59 SD 5.19 SD 5.89 SD 6.49 SD 7.09 SD 7.59 SD 8.19 SD 8.69 SD 9.09 SD 9.59 SD SD SD Braid Our ideas of color are often limited to what we apply to fiber. Understanding the underlying natural tones allows us to create more sophisticated textiles, either naturally colored or dyed. Color(s) Wool can, of course, be dyed in unlimit colors. Its natural hues range through grays, browns, and occasional red and gold shades. Even in whites, though, colors vary, with some warmer (as in the Bluefaced Leicester shown here) and some snowier (like the Leicester Longwool). Dyeing over natural colors, like that of the brown Border Leicester, can produce elegant results. Bluefaced Leicester Leicester Longwool Border Leicester 7

8 Qualities that aren t usually measured Dorset Down American Tunis American Tunis When the feel and behavior of a fiber are at odds with what that fiber is supposed to be like, trust your fingers. These yarns were wrapped around the same niddy-noddy. Then the skeins were washed. One wool has more loft and elasticity than the other! Among the qualities relating to wool that are not often measured are elasticity; flexibility; and personal sensitivity. Mechanical and chemical analysis can yield a lot of useful and intriguing information about wool fibers. These details serve invaluable functions in industrial processing. Most people working with fibers in hand processes don t have access to analytical data, nor do we need it, except to refine our understanding. For tens of thousands of years, people have simply gathered wool and worked with it, making samples and then fabrics. In the twenty-first century, we can do this, too. What I m presenting here are the ways I think about wools. Some of the terms I am using (especially those for lock shapes) are not standardized, but are the ways I begin to classify a fiber I m observing. There are many gray areas in between these: wools that have intermediate or mixed characteristics. Wool is infinitely variable! 8