This is Snowflake #38 in the book of 100 Snowflakes. Instructions are on Page 64. It is pictured on page 28 in the showcase.

“This pretty, compact snowflake might have fallen in a rare winter thunderstorm.”

Finished diameter: 2 3/4 in (70 mm)
Thread required: 8 yd (7.3 m)

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