The shell stitch can be worked in every type of material from the finest cotton thread to bulky weight yarn. There are many variations on the shell pattern from open and lacy to quite closed and dense. Since afghans are usually intended to be used for warmth, denser stitches are usually preferred.
Basic Shell Stitch
The basic shell stitch usually consists of a starting chain in multiples of three plus two. The first shell consists of three double crochet stitches in the sixth chain from the hook. The next two chain are skipped, and three double crochet are made in the next chain and the pattern continues in this way across the first row.
At the end of the first row, double crochet in the last chain, chain 3 and turn. In the second row three double crochet are made in the second double crochet of the first row and in the second double crochet of each shell across, double crochet in turning chain of previous row, chain three and turn. The basic shell pattern results in an open weave, but may be used for afghans.
The Closed Shell Stitch
Like the basic shell stitch, the closed shell begins with a chain in multiples of three. Make three double crochet in the fourth chain from the hook, skip two chain, slip stitch chain three in the next chain and make three double crochet in the same chain.
The pattern is repeated across from skip two chain. At the end of the row, chain five and turn. In the second row, slip stitch in the first chain three, chain and make three double crochet. Continue with a slip stitch chain three, three double crochet in each chain three space across. Join the last shell with a slip stitch to the third chain of the turning chain of the previous row, chain five and turn. Repeat row two.
The closed shell stitch results in a dense, closed weave with a basket weave appearance. It is ideal for afghans and can be worked in any size yarn. When worked in single row stripes of different colors, each shell has a diamond shape which makes the pattern interesting.
The closed shell stitch is great for beginners and those at an intermediate level and works up quickly, especially in bulky weight yarns with a K or L hook. It will make a warm and attractive afghan and can easily be mixed with other stitches for additional interest.