This is pattern #15 in the book “100 Lace Flowers to Crochet.” Instructions on page 53. Featured on page 25 of the showcase.

Finished diameter: 1-1/4 inch (32 mm)
Thread required: 1 yard (0.9 m) of center color; 3 yards (2.7 m) of petal color.

All pattern samples in this book are made with size 10 thread and a size 5 (1.9mm) crochet hook.