Probably within the last 30-40 years, since they are inscribed by lasers. Initial documentation about using lasers in the diamond industry is dated in the early 1980s.
No, but a diamond is.
You have spelled it correctly: diamond.
Diamond.
Because it looks similar. But it DEFINATELY IS NOT A DIAMOND. A diamond is never used in math. A rhombus is an actual geometric shape, unlike a diamond.
Debeers
DeBeers are the diamond people in South Africa, they mine and they also broker, in one word they have the monopoly on the diamond industry, they are world famous, when you say "DeBeers" you know you mean diamonds.
DeBeers controls about 35% of the diamond gemstone industry, according to Time Magazine, November 2010.
The DeBeers diamond empire began in 1837 with the discovery of a Diamond mine in Africa. The DeBeers popularized the use of diamonds as a stone signifying commitment..
Probably the DeBeers organization.
This slogan began with DeBeers in the 1930s.
It makes money for the Debeers family.
Wholesale and to the trade, the largest supplier is probably DeBeers.
The De Beers Group is considered the first major diamond company. It was founded in 1888 by Cecil Rhodes and played a significant role in the diamond industry's growth and marketing strategies.
The largest collection is probably in the hands of the DeBeers diamond organization.
Cecil Rhodes, an Englishman, formed the DeBeers diamond organization. According to Wikipedia, as below, his partner was C.D. Rudd. The name DeBeers was the family name of the farm they purchased that contained the volcanic pipe. You can read more about Rhodes, below.
In this film, the diamond cartel pursuing acquisition of the pink stone may be loosely based around the DeBeers organization, but with a different name. DeBeers has not confirmed or denied the suggestion that a disclaimer be inserted into this film's credits, denying that DeBeers served as a model for this company. Read more, below.