Shades of cyan are blue, green, and red.) As such, the CMYK printing process was invented in the 1890s, when newspapers began to publish color comic strips. Process cyan is not an RGB color, and there is no fixed conversion from CMYK primaries to RGB. Different formulations are used for printer's ink, so there can be variations in the printed color that is pure cyan ink. A typical formulation of "process cyan" is shown in the color box at right. The source of the color shown at right is the color magenta that is shown in the diagram located at the bottom of
Early American editions of The Hobbit 14th impressions come in a variety of colors. Generally all the books from one printing are bound in the same color, but exceptions may have been found, perhaps when bindings intended for one printing were left over and found use at the beginning of the next printing. Hence the color of the covers cannot conclusively identify a book. The 6th impression's blue-green is medium light and distinctly blue. The 7th impression's khaki binding, on the other hand, shows no hint of blue or green. Its color is considerably darker than the 10th through 12th impressions. The rust color of the