[FONT="Comic Sans MS"][COLOR="#300090"]Catlvr,
I think you have a good start on the pattern with one exception. :think: Row one appears to be different from the other four rows. I think it is a ch 3 sk 3 gap and there are only five rows that repeat 1,2,3,4,5,4,3,2,1 for the length desired.
Length will be multiples of ten plus two chains and plus chains for your turning chain (which will count as first dc of next row.) (Isn't it two chains for a dc turn?) This pattern is for a swatch three diamonds wide, so it would need a 35 chain foundation. (Note: I added one more ch for the half gap that starts row one.)
DC in sixth chain from hook dc in next 7 chains, ch 3 skip next 3 repeat from * to * once more then finish with 7 dc in next 7 chains ch 1 sk 1 dc in last chain.
ch 2 (counts as first dc), * ch 2 sk 2, dc in next 5 dc, ch 2 sk 2, dc * repeat to end of row.
ch 2 (first dc), dc in first chain, * ch 2 sk 2, dc in each dc next 3 st, * repeat four more times (until one dc and ch4 remain at end of previous row), ch 2 sk 2, dc in 2nd chain remaining, dc in third chain remaining (top of the ch2 that counts as previous rows first dc).
Ch 2, dc in next 2 st of previous row, * ch 2 sk 2, dc in center dc of peak, ch 2 sk 2, dc in next 5 st, * repeat between * twice more, finish with dc in last peak, ch 2 sk 2, dc in each of last three st of previous row (ch, dc, & top of ch 2).
ch 2, dc in next three st, * ch 3 sk 3, dc in next 7 st, * repeat once between *, ch 3 sk 3, dc in each of last four st of previous row.
Repeat rows in the following order * 4, 3, 2, 1, 2, 3, 4, 5 * and then repeat that pattern of row until length of afghan is reached.
I would end on a row 1 repeat.
I do not recognize the edging other than it is a ruffle.
I would try ...
sc in each stitch across end, * 2sc in corner, two sc for each row along row ends, * 2 sc in corner, sc in each st across starting ch/row, repeat between * for remaining side, join to first edge sc with sl st.
Ch 3 (counts as first dc and ch 1), dc in same st as sl st, ch 1, * dc, ch 1, dc in next sc, ch 1* repeat between * for each sc around sl st to 2nd chain that started round.
Dc, ch1, dc in each st round, join with sl st as with round 2, cut yarn and weave in end.
That is my best guess. Use a ruler to measure the existing afghan for gauge and select yarn and hook sizes to match gauge.
Does that sound and look about right?
(:think: It might be better to rework the pattern to start and end row 1 in the middle of each diamond pattern rather than with the gaps.)