30 gr DMC Cebelia Art. 167, size 30
Hook size 10, international 1 mm

Rounds 1-3 = 1.75” (4.5 cm)

Challenging.
Breaks twice. Not a straight-edged circle.

Pattern 19, pg 40 in Magic Crochet.
Called Snowflakes in Crochet Monthly.
Shown on cover of Puntorama Ganchillo.