Yellow placemats

I made these using a pattern from a crochet book from the 1970s I bought for $1.50 at the local library book sale.  Of course, I altered it as usual.  I though they were cute.  I made a set of six with crochet thread to put sell.  I also made a set for my brother and sister-in-law out of worsted weight acrylic yarn.  I have for sale on Etsy (http://www.etsy.com/listing/77961548/6-yellow-lacy-crocheted-placemats-or) and Madeitmyself (http://www.madeitmyself.com/item-detail.aspx?itemid=71493)  if anybody is interested.
I've been trying make up a pattern for the same kind of circle with the diamonds but with it going in a spiral instead.  I just can't figure it out!  Out of all the different things I can do with crochet, I can't get spiraled diamond circles figured out!  It's making me feel less confident in my crocheting abilities!  Ugh, I'll figure them out someday!
Anywho... here are the placemats!