According to the book, The Engagements by J. Courtney Sullivan, the phrase was coined by:
". . . Frances Gerety, who was a copywriter with the Philadelphia ad agency N.W. Ayer and Son beginning in the 1940s."
The agency client was DeBeers.
This slogan began with DeBeers in the 1930s.
A female marketing executive at DeBeers created the tagline "a diamond is forever" around 1940 ... they have stuck with the slogan and successfully marketed it since that time.
quel est la slogan de diamond bank
The slogan is "Zales: The Diamond Store."
According to Wikipedia, the DeBeers slogan... "A young copywriter, Frances Gerety, coined the famous advertising line "A Diamond is Forever" in 1947, allegedly while she was dreaming." The line may refer to the age of the diamond mineral, which takes, in alluvial mines, from 10,000 years to 1.8 million years to form, according to the KHI Web site. As well, she may have wanted to infer that once the gift of a diamond is received, a promise of 'forever' is implied as a reference for the impending relationship.
Faith.Fashion.Forever21
nook
Forever Young!
Yes, the slogan is "When you can live forever, what do you live for?" It encapsulates the central theme of immortality and searching for purpose in life.
faith, fashion and forever 21
The DeBeers Organization uses this slogan. You can see it on their home page, below.
Wales's slogan is 'Cymru Am Byth', which means 'Wales Forever'.