Why Are So Many Pencils Painted Yellow?
Natural wood, black, and dark red were once common pencil finishes. The yellow pencil became familiar after one European manufacturer used the color to advertise an unusually expensive product.
During the nineteenth century, pencil makers competed over the quality and consistency of their graphite. The Hardtmuth company, then operating in the Austro Hungarian Empire, introduced a premium pencil called the Koh I Noor. Its name came from the famous diamond whose Persian name means Mountain of Light.
The company painted the pencil yellow, making it immediately different from many competitors. The precise reason for the choice was not recorded clearly enough to remove all doubt. The most repeated explanation connects it with the prestige of Asian graphite and with yellow's imperial associations in China. What can be established more confidently is that the yellow Koh I Noor became an international commercial success.
The pencil won recognition at major exhibitions and was marketed as a superior writing instrument. Other manufacturers, particularly in the United States, began producing yellow pencils of their own. The color gradually became associated not with one company, but with a dependable graphite pencil.
Yellow also offered practical advantages. It was bright, recognizable, and provided a strong background for dark printed branding. By the twentieth century, manufacturers had reinforced the association through enormous production for schools and offices.
Not every pencil is yellow, and many countries developed different conventions. Yet the classic American school pencil still carries the visual legacy of a European company trying to make one premium product look as valuable as a famous diamond.
Source: History of Company, Koh I Noor Hardtmuth - The Pencil: A History of Design and Circumstance, Henry Petroski

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