Their method was really astute. They collaborated with N.W. Ayer, a New York advertising firm, to develop the slogan "a diamond is forever." As a means of advertising, Ayer took use of both famous people and the rising popularity of movies. Diamonds were often given as symbols of everlasting love in Hollywood films. In advertising shots, actresses and models often wore flashy jewellery, especially diamonds.
De Beers' monopoly on the diamond industry's supply chain is eroding in the present day. Despite this, prices continue to grow since no new resources have been discovered lately, and demand for diamonds is booming in India and China.