This hexagon (which can be used as either an applique or a lace block) is pattern #41 in the book “75 Lace Crochet Motifs.” Instructions on page 77. Featured on page 27 of the showcase.

Finished diameter: 3 inches (76 mm).
Thread required: 12 yards (11 m).

All pattern samples in this book are made with size 10 thread and a size 7 (1.65 mm) crochet hook.