Yarns and Threads

Choosing the right type of yarn is essential for the look, feel, and usage of your project.

Protein Fibers, such as angora, cashmere, mohair, silk, wool are from animal hair, or insect cocoons, and absorb humidity.

Natural Cellulose Fibers are from plants, such as cotton, flax, or hemp, absorb humidity, and are strong.

Regenerated Cellulose Fibers are man-made, and now classified as natural fibers, such as rayon, lyocell, cellulose acetate.

Synthetic (man-made) Fibers are chemically changed substances to act like fibers, such as nylon, polyester, acrylic, polypropylene. Elasticity and strength are their characteristics.

The Weight of Yarn

Spin tells how the fibers are put together during their spinning production determining its tightness.

There are several systems on the market to classify yarn.

One system classifies by the diameter of the yarn:
A = fine-weight yarns… e.g. light baby clothes
B = medium-weight… e.g. dresses, sweaters
C = worsted-weight… e.g. jackets, hats, mittens, blankets
D = bulky-weight… e.g. heavy jackets, crafts
E = extra-bulky-weight… e.g. rugs, crafts

Another system classifies by the number of stitches per 4-inch:
1 = fine… 29-32 stitches
2 = light… 25-28 stitches
3 = medium… 21-24 stitches
4 = medium-heavy… 17-20 stitches
5 = bulky… 13-16 stitches
6 = extra-bulky… 9-12 stitches

Lace-weight yarns are ultra-fine and in neither of two systems above.

Worsted Yarns, predominantly used for socks, is smooth and tight.

Wool-spun yarns, predominantly used for hats, jackets, are soft and airy.

Specialty or novelty yarns have various different looks and feels, such as fuzzy yarn, lacy yarn.

Crochet Hook Sizes

Now-a-days crochet hooks are made of steel, aluminum, wood, and plastic.

The size of a crochet hook is determined by it’s diameter of the shaft. There is no international standardizes size set yet. The metric sizing is mostly used mostly in Europe and the letter/number sizing in the United States. Each country has its own hook sizing. There is an effort on its way to standardize the crochet hook sizes. When in doubt use a metal hook gauge to determine its size.

The steel hooks are used preliminarily for threads. The sizes are  from 0.75mm to 3.50mm and/or numbering 14 to 00.

Aluminum, wood, or plastic hooks are used for yarns. Former times crochet hooks were made of an array of materials like: bamboo, bone, brass, horn, ivory, mother of pearl, pewter, silver, tortoise shell, woods. The sizes are from 2.25mm to 15.00mm and/or capital lettering from B to Q.

Sizes of Crochet Hooks
Crochet Hook Size List

There are a variety of books on the market that have detailed information on crocheting if you would like to learn more. My preferred reference book is “Encyclopedia of Crochet ” by Donna Kooler with historic background, crocheting terminology and symbols, a visual introduction on crocheting, crochet patterns and projects.