When was the slogan "A diamond is forever" first introduced?

The slogan "A diamond is forever" was first introduced in the 1940s as part of an advertising campaign by the De Beers diamond company. This phrase was created by the advertising agency N.W. Ayer and has since become one of the most recognizable slogans in marketing history. The timing was significant, as it was designed to reinforce the idea of diamonds as symbols of lasting love and commitment, particularly in the context of engagement rings. This concept played a crucial role in shaping consumer perceptions and behavior regarding diamond purchases, establishing diamonds as the traditional choice for engagement. The association of diamonds with eternity and lasting relationships helped to boost diamond sales during that era and has continued to influence the jewelry market to this day.