"Color variations" refers to differences in shades or tints of a particular color. It means that there can be slight or noticeable differences in the hue, intensity, or saturation of a color, usually found in objects or materials. Full definition
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There are about 60 different color variations of this breed. (tips-for-cats.com)
Even the snow and ice glow with subtle color variations in the pleasing digital collage artwork, which combines painted, drawn, and printed elements. (booklistonline.com)
This geometry hides shadows and reveals subtle color variations. (sciencedaily.com)