Sewing pattern instructions tells you to use silk or crepe. The first is a fibre type and the second a type of a weave. Here's some help to the confusion.
10 different types of fabric that you should recognize with your fingertips! < with my hands - Dream
Types of African Print Fabrics You Should Know Of
Custom Soft Window Treatments to the Trade - Carole Fabrics
Named Earth Science sewing pattern collection < with my hands - Dream
Fabric for Fashion - a book review < with my hands - Dream
Kokkola costume, part 2: An apron with drawn thread embroidery < with my hands - Dream
Fabric science: 10 types of fabric you should know - Luftkuss Atelier
A folk-style pocket < with my hands - Dream
Ultimate Guide to Sewing with Knit Fabrics
Fabric Types to Sew - Melly Sews
Types Of Fabrics, Everything You Need To Know