I have been creating a small library of filet crochet swatches recently, including filet crochet small diamonds pattern, filet crochet diamond trellis pattern, filet crochet diagonal stripes pattern, and now presenting the filet crochet diamonds pattern, and I only wish I hadn't run out of yarn so that I could have crocheted a larger swatch! Each pattern has a slightly different "fall" to it depending the density of the double crochet stitches, and while this swatch is small, it has a great feeling to it, and hoping to crochet a larger swatch soon! And as I've mentioned these swatches are currently in use in either my 1/8 scale dollhouse (currently for a family of stuffed rabbit dolls) where they make great blankets, or in my 1/12 scale minimal scandi style dollhouse where they are great rugs and large blankets. I love crocheting with mercerized cotton and a 3mm hook, basically because that is the yarn that is readily available here in Israel.
Are you sold? Truthfully this stitch could also be used as a border for a number of projects, or a table runner? Regardless use the summer to delve into crochet!
My swatch was crocheted with mercerized cotton and a 3mm hook, and a base chain of 52 plus 4. Sorry about the poor quality diagram, that is all that I could find, but a simple pattern, so give it a try!