This is Snowflake #3 in the book of 100 Snowflakes. Instructions are on Page 45. Picture is on Page 22 in Showcase.

“A stellar crystal is a flat, star-shaped ice crystal; in other words, a perfect snowflake.”

Finished diameter: 2-7/8 in. (73 mm)
Thread required: 5 yd (4.6 m)

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