yarn by JunoFibreArts on Etsy
NOTE: THIS INFORMATION IS PUBLISHED ON THE UK WOOLLEN DIRECTORY:
Wool is fibre from a domesticated sheep. Wool accepts dye well, is flame-retardant by nature, remains warm even when wet, sheds water better than other yarns. Natural wool should be hand-washed. 'Superwash' wool has been treated to allow machine washing. Wool will usually resume its proper shape when washed correctly; if it is mistreated and washed in too-hot water, it will shrink or felt.
Mohair is fibre from an Angora goat. Mohair is durable, sheds dirt, dyes well and does not felt easily. Despite its hardiness, it is usually spun into yarn used for fluffy garments and scarves. This yarn is abraded, roughing its fibres to create that 'fuzzy' look.
Angora is fibre from rabbits. Fabric made from this yarn is inelastic (no stretch), very fluffy, soft and warm.
Silk is the fibre produced by silk moths. Silk knitting yarn is made from damaged silk cocoons and broken fibres. 'Raw' silk still has the original moth secretions in it. 'Tussah,' silk obtained from wild moths is brown. The food fed to domesticated moths determines their silk's natural colour; this can be white, green or yellow. Silk retains heat, absorbs moisture, pills less than wool, is very strong and very stable when knit, neither shrinking or stretching.
Cashmere is fibre from the undercoat of a Cashmere goat. It is so expensive because only a few ounces are obtained from each goat per year. It is such a delicate yarn, more fragile than wool and more susceptible to abrasion, that it is usually blended with wool to make it more durable.
Camel is fibre from the two-humped or Bactrian camel. Camel hair cannot be bleached, so it is either used undyed or dyed a darker colour. It is lightweight and fragile.
Vicuna comes from the vicuna, a South American relative of the camel. They are rounded up once a year and shorn like llamas or sheep; their hair is finer than any other animal fibre.
Alpaca is a smaller relative of the llama but its hair is more commercially valuable. Yarn from this fibre does not felt or pill easily. It comes in fifteen natural colours (as do the alpacas) and is denser than wool, so fabric knit from it may droop. The undercoat of a llama is very similar to alpaca hair.
Cotton is the fibre surrounding the seeds in a cotton pod. Usually white but there are green and brown varieties. Cotton is heavy, dense and inelastic; although it will regain its shape after washing, its ability to do so decreases over time. It is comfortable to wear in a cool climate but not a hot one (the opposite of wool) and is slow to dry once wetted. It makes a weaker yarn than silk or linen but is stronger than wool.
Linen comes from the flax plant. It is durable and stronger than any other fibre. Fabric made from it becomes softer and more beautiful with age. It absorbs moisture better than cotton and dries more quickly, making it more comfortable to wear than cotton in hot temperatures. It is easier to wash than wool and does not stretch or shrink.
Information taken directly from the UK Woollen Directory website.