This is Snowflake #2 in the book of 100 Snowflakes. Instructions on Page 44. Pictured on page 22 in Showcase.

“You might find ice crystals like this one decorating your window on a late fall morning.”

Finished diameter: 1-1/4 in. (44 mm)
Thread required: 4 yd (3.7 m)

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