The 7 cards in the magician’s hands are 7 colors. Sound obvious? Look deeper. The 5 color cards in the middle appear to your eyes as if they are gradients.
The dictionary definition (of the word “Halation” fails horribly

Halation is Not Magic, rather it’s…

Halation: The Single Most Important Law of Color

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A pile of color swatches were placed in front of us and we were told to organize them. We slid the paper color squares around on the table, trying to find relationship. As we would learn, we were ordering families of color. Each array was made up of two parent colors and their children.

Once arranged, the steps, from one color to the next is perfect step — a proportional mix or blend of the parent colors.

Color harmony, often considered intuitive, can be hacked.

A great insight occurred when my teacher held in his hand three cards.

Only two colors were visible.
The red (more of an orange-red), behind the yellow.

Two cards were visible, red (more of a “red-orange-red”) and yellow (more of an “orange-yellow”).

As if teaching the rules of a card game, my professor leaned in to show me his hand.

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