This is the first of a series of posts about color mixing.
All of the kaleidoscope designs on the left have three things in common: (1) They were made from same canes I used to cover the eggs. (2) The component canes were all constructed using Skinner Blends. And most importantly for this post (3) All of the colors you see were mixed from the same three colors of Premo clay, plus white. (Caveat: In a few cases, black was used to outline the component canes.)
What colors of clay were they? Well here are the clues…
Clue #1. The designs include colors from all over the spectrum. This tells us that all three primary colors, red, yellow and blue were used. But which ones? Premo has two reds – Cadmium Red and Fuchsia; three blues – Cobalt Blue, Ultramarine and Turquoise; and two yellows – Zinc Yellow and Cadmium Yellow. [Two of these colors, Cobalt Blue and Zinc Yellow have been taken off the shelves of craft stores, but they can be purchased on the internet and are essential for color mixing so they are included here.]
Clue 2. Notice that the purples are vibrant, like rainbow colors or gem stones. (Another word for this vibrancy is “saturated.”) This is a tip off that the red used to mix the purple was “Fuchsia,” not “Cadmium Red”. 
Cadmium Red yields muddy (desaturated) purples when mixed with blue.
The first thing I check when I’m going to mix colors to match a picture is whether the purples in the picture are saturated. That tells me immediately which red to use.
Clue 3: The yellow in the design above on the right is lemony rather than golden. This tells me that Zinc Yellow was used rather than Cadmium Yellow.
Cadmium Yellow has what we call “undertones” of red while Zinc yellow has no perceptible undertones. If you were to mix the tiniest bit of Cadmium Red with a whole lot of Zinc Yellow, the mixture would look nearly identical to Cadmium Yellow. Cadmium Yellow, on the other hand cannot be modified to look like Zinc Yellow. There is no way to take out the red undertones. The brightness of the oranges is another clue. If Cadmium Yellow, instead of Zinc Yellow, had been mixed with Fuchsia the oranges would have been duller.
Clue 4: We have identified the red (Fuchsia) and the yellow (Zinc Yellow). All we have left to identify is the blue. Just by looking at the purples, we can tell that Turquoise wasn’t used. Premo Turquoise (which contains some white) mixed with Fuchsia yields a soft, tropical looking purple, not the deep, rich purples we have here.
That leaves Ultramarine and Cobalt Blue. Discerning between these two can be tricky because the differences are more subtle. This is a situation where practice in color mixing comes in handy. I know from experience that Cobalt Blue yields brighter greens than Ultramarine, which is a darker blue and has red undertones. The colors you see here were mixed from Cobalt Blue. Another clue is that I can actually find Cobalt Blue in some areas of the designs. Cobalt Blue can be modified to look like Ultramarine, but Ultramarine can’t be modified to look like Cobalt Blue because you can’t take out its red undertones.
This triangle consists of Skinner blends from Zinc Yellow to Cobalt Blue to Fuchsia and back to Zinc Yellow. This triad yields the purest, most saturated and vibrant blends of any 3 Premo primaries. Not only that, within the blends you can find hues that approximate the other primaries: Cadmium Red, Cadmium Yellow, Turquoise, and Ultramarine. This would not happen with any other combination of primaries.
(Which primaries did Polyform take off the shelves of craft stores? Zinc Yellow and Cobalt Blue, two of the purest primaries. Two colors that cannot be approximated by mixing any of the others.)
(To be continued in future posts…)
