From the label

Cellulose yarn “for knitting or crochet”.

Celanese
Standard & Crepe Twist
Made only by British Cellulose & Chemical Mfg. Co. Ltd.

Appearance: It has a dainty texture, softness and lustre. It is wonderfully silk-like to handle.

Washing: Repeated washings actually improve the lustre and strength. It washes perfectly.

Wearing: It is extremely durable and has the unique property of being cool in summer and warm in winter.

Washing: Use warm water and “Lux”. Rinse only. Do not rub.

Drying: Do not hang garment up. Roll or lay out flat.

Ironing: Cool iron and dry cloth.