The color portion is cotton DMC thread -- two strands held together so that shading could be produced. I wanted a rainbow effect, so my base colors were Red Orange Yellow Green Blue Violet.
Inbetween shades were then produced by holding together adjacent colors. That is Red + Orange, Orange + Yellow, Yellow + Green, Green + Blue, Blue + Violet, and Violet + Red.
Each colored pattern was surround by a simple beige cotton sport yarn.
I tried several ways of placing the motifs but I really wanted the classical rainbow order of ROYGBV. I like the look of moving the motifs over 1 space for each line. A friend drew dark lines between the motifs so I could see how a darker joining cotton would look.
I opted for the same beige yarn to join the motifs in order to keep the illusion of gradual changes.
Note: this took several years to complete because I take along motifs when I travel.
05-21-2022
Finally found a source for very similar motif in the color portions. Not in the Crochet Calendar but in a book published in 2015. I made this 6 years before the book was published. The only change is my final round had 5DCs; this pattern has 6 DCs
Motif pattern store in private google drive
https://drive.google.com/file/d/1motGhuyERyViC02Cz_1tEC7I...
05-27-2022 Squaring the Round and Joining
Squaring the Round
There are 8 shells from the final round of the motif. Each shell has 5 DC.
Join at the crest of one of the shells from prior row -- the third stitch.
Do SC in that third DC. CORNER: Then HDC in next stitch, DC in Next stitch, TC in Next then QC (3 wraps). Create corner with 2 SC. Then QC, TC, DC, HDC and SC in top of next crest.
SIDE: The next stitches create a shell in the valley between crests. TC, DC,DC, TC. Then SC in crest of next shell.
Repeat CORNER and SIDE til done
Joining motifs was done using all SC.
Create strips from top to bottom.
Lay strips side-by-side and connect down the sides
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