Pattern recommends 80 grams of no. 30 crochet cotton and a 1.00 mm hook. Finished size is 82 cm (32 ins) diameter.

Pattern 13, Pinwheel Table Center, in Magic Crochet #29.
Pattern 14, Whirlpool Table Mat, in Crochet Monthly #66.

There is a similar pattern in Magic Crochet #30 and Crochet Monthly #53, but it has a different center.

#pinwheel