What is pearl cotton?
Also called perle cotton, it is a mercerized twisted, non-divisible, lustrous 100% cotton thread. It is always sold in a skein, and available in five weights: No. 3, 5, 8, 12 and 16. No. 3 is the heaviest kind, while 16, or Finca, is the finest. The thread is commonly used in embroidery as well as wool applique, and almost always for hand needlework as opposed to machine embroidery.