This is Snowflake #94 in the book of 100 Snowflakes. Instructions are on Page 103. It is pictured on Page 38 in Showcase.

“This elegant crystal could be blown away on the Buria, a Bulgarian term for a cold fall wind.”

Finished diameter: 4 in. (102 mm)
Thread required: 13 yd (11.9 m)

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