where do most of the worlds diamonds come from
Diamond Diamonds are far from evenly distributed over the Earth. A rule of thumb known as Clifford's rule states that they are almost always found in kimberlites on the oldest part of cratons, the stable cores of continents with typical ages of 2.5 billion years or more.[14][19]:314 However, there are exceptions. The Argyle diamond mine in Australia, the largest producer of diamonds by weight in the world, is located in a mobile belt, also known as an orogenic belt,[20] a weaker zone surrounding the central craton that has undergone compressional tectonics. Instead of kimberlite, the host rock is lamproite. Lamproites with diamonds that are not economically viable are also found in the United States, India and Australia.[14] In addition, diamonds in the Wawa belt of the Superior province in Canada and microdiamonds in the island arc of Japan are found in a type of rock called lamprophyre.[14]
Eternity ring The concept of the diamond eternity ring was created in the 1960s by diamond merchant De Beers.[3][4] American investigative journalist Edward Jay Epstein stated that at the time the company had a secret agreement with the Soviet Union which, in return for the creation of a "single channel" controlling the world's supply of diamonds, 'required' the purchase of 90-95% of the uncut gem diamonds produced by Russia.[4] The prevailing fashion at the time, particularly for engagement rings, was for them to be set with a single, large diamond. The Soviet gems, however, were small, often less than 0.25 Carats.[3] To avoid stockpiling, De Beers embarked on a campaign of promotion of jewelry containing a number of small diamonds culminating in the eternity ring, which was aimed at older, married women.[3] One campaign slogan, aimed at husbands, was "She married you for richer or poorer. Let her know how itâ€™s going."[5] The idea proved popular with the public, and sales continue to be significant.