Here's the pattern for the flat heart I've designed for my wedding invitations. The red one in the picture is slightly more angular than the finished pattern, but I stuck it to a prototype invitation so I photographed the original version.
The large (pink) heart was knit on 3mm needles with baby double knit (to the original 'large heart' pattern).
The small (red) heart was knit on 3mm needles with double knit (to the original 'large heart' pattern). The 'small heart' pattern allows baby double knit to create the same size as this heart.
I don't know why the babyDK seems to have knit up so much bigger than the DK, but I don't have the label for the DK so I can't tell you its properties. Sorry!
Large heart:
If knit in baby double knit this knits up at the size of the pink heart in the photo.
If knit in double knit it knits up at the size of the red heart in the photo.
*CO 3sts
K 2 rows
Inc 1, K to end of row (repeat this row 5 more times)**
Break yarn and leave on needle
Repeat from * to **, casting on same needle sts have been left on
K across both pieces
K row
Inc 1, k across row, inc 1
K 2 rows
# K2tog, k across row, k2tog
K row ##
Repeat from # to ## until 3sts remain
Slip 1st st knitwise, k next st and pass 1st st over (as cast off), k last st, pass 2nd st over.
Break yarn, fasten off, bury ends.
Small heart:
This pattern is for use with baby double knit. Using double knit will create a much smaller heart.
*CO2sts
K 1 row
Inc1, k to end (repeat this row 4 more times)**
Break yarn, leaving stitches on needle.
Repeat from * to ** (casting on to same needle sts have been left on)
K across both pieces
K 1 row
Inc 1, k across row, inc 1
k 1 row
# K2tog, k across row, k2tog
K row ##
Repeat from # to ## until end.
Cast off, break yarn, fasten off, bury ends.
