By 1965, 80 percent of American women had diamond engagement rings:
...it wasn't until the late 19th century, after the discovery of mines in South Africa drove the price of diamonds down, that Americans regularly began to give (or receive) diamond engagement rings. (Before that, some betrothed women got thimbles instead of rings.) Even then, the real blingfest didn't get going until the 1930s, when—dim the lights, strike up the violins, and cue entrance—the De Beers diamond company decided it was time to take actionMeghan O'Rourke/Slate
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In 1919, De Beers experienced a drop in diamond sales that lasted for two decades. So in the 1930s it turned to the firm N.W. Ayer to devise a national advertising campaign—still relatively rare at the time—to promote its diamonds. Ayer convinced Hollywood actresses to wear diamond rings in public, and, according to Edward Jay Epstein in The Rise and Fall of the Diamond, encouraged fashion designers to discuss the new "trend" toward diamond rings. Between 1938 and 1941, diamond sales went up 55 percent. By 1945 an average bride, one source reported, wore "a brilliant diamond engagement ring and a wedding ring to match in design." The capstone to it all came in 1947, when Frances Gerety—a female copywriter, who, as it happened, never married—wrote the line "A Diamond Is Forever."
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Due to advertising campaign, artificially induced fad, parallel to the artificial insertion of cigarette smoking into the cultural flow - thru Hollywood subliminals and massive focused advertising campaigns - by 1947 diamond demand is way up.
Apartheid begins in South Africa with the election of the Nationalist Party in 1948
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The Rt Hon Cecil John Rhodes DCL was an English businessman, mining magnate, and politician in South Africa. Rhodes was named the chairman of De Beers at the company's founding in 1888.Wikipedia
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In October 1871, 18-year-old Rhodes and his brother Herbert left the colony for the diamond fields of Kimberley. Financed by N M Rothschild & Sons, Rhodes succeeded over the next 17 years in buying up all the smaller diamond mining operations in the Kimberley area. His monopoly of the world's diamond supply was sealed in 1889 through a strategic partnership with the London-based Diamond Syndicate.
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The British financiers who had organized the South African mines quickly realized that their investment was endangered; diamonds had little intrinsic value—and their price depended almost entirely on their scarcity. The financiers feared that when new mines were developed in South Africa, diamonds would become at best only semiprecious gems. The major investors in the diamond mines realized that they had no alternative but to merge their interests into a single entity that would be powerful enough to control production and perpetuate the illusion of scarcity of diamonds. The instrument they created, in 1888, was called De Beers Consolidated Mines, Ltd., incorporated in South Africa. As De Beers took control of all aspects of the world diamond trade, it assumed many forms. In London, it operated under the innocuous name of the Diamond Trading Company. In Israel, it was known as "The Syndicate." In Europe, it was called the "C.S.O." -- initials referring to the Central Selling Organization, which was an arm of the Diamond Trading Company.Edward Jay Epstein/Atlantic
