Many materials, including torn fabric strips and leather cords, can undergo transformation into a completed project, but this guide focuses on the most common crochet material: yarn. Choosing a project’s appropriate yarn based on weight previously posed confusion; however, the Craft Yarn Council of America created a classification system, which most yarn manufacturers and publishers of crochet books have adopted and turned into an industry standard.
The industry labels yarn according to one of seven classifications indicated by the category name or a number symbol.
Cotton crochet thread also falls within this category. Use this for fine, delicate projects such as tatting or creating lacy, open shawls, tablecloths, placemats, and doilies.
Super Fine, #1
Manufacturers sometimes label this yarn as fingerling or baby yarn. Use this for projects such as baby blankets and clothing, socks, and shawls more substantial than those of lace.
Manufacturers sometimes label this yarn as sport or sport weight yarn. This weight works well in creating light sportswear, shawls and wraps, accessories, and light sweaters.
This category includes double knitting, often represented as DK, and light worsted yarn. Use this yarn for adult and baby clothing and for light throw blankets.
Classified as medium, this yarn most often carries the labeling of worsted, afghan, or aran. Worsted weight yarn has the greatest popularity and amount of uses of all the various yarns. Beginning crocheters find this the easiest yarn weight with which to learn.
The vast majority of crochet hooks indicate the size on a slightly flattened area in the center of the hook’s body. The size of crochet hooks differs according to three variables: the hook’s manufacturer, country of origin, and material.
With very few exceptions, crochet patterns will indicate the size of hook required for the project; however, keep in mind that the hook size suggested by old patterns may differ modern, standard hook size. If there exists any uncertainty regarding hook size, crochet a small test piece and adjust to a larger or smaller hook as the measurement or gauge indicates.
Crochet hooks must match the material component of a project. Pair the larger hooks with thick, bulky yarn and the smaller hooks with fine, thin material. The common materials used to make crochet hooks are steel, plastic, and aluminum. Use steel hooks, smaller than plastic or aluminum hooks, for projects with fine thread or tatting cotton, and use aluminum or plastic hooks for projects with yarn.
As experience with crochet develops, projects may require specialized hooks, such as lace needles, jumbo wooden hooks, and double-hook needles, but these implements are not must-have items.
Most hooks will display one of the numbers or letters as shown on the following charts.