One of the most popular questions jewelry buyers ask is: how are diamonds formed?
The history of diamonds dates back at least 2.5 billion years, according to most geologists. They form below the earth’s surface at a distance of 75-120 miles below the surface, under conditions of intense heat, between 900 and 1300 degrees Celsius, and pressure.
How are Diamonds Formed?
Diamond formation comes from three acts being performed together: carbon, pressure and heat, in either the man-made formation of diamonds or the formation of natural diamonds. In the case of the formation of natural diamonds, there is a ton of carbon already in the earth. It begins to crystallize through pressure and heat; eventually after diamond formation, it begins to rise to the surface through eruptions of volcanic pipes.
Common shapes created in the formation of natural diamonds are octahedrons and rhombic dodecahedrons. After diamond formation, the resulting raw diamonds can be found near volcanic pipes or placer deposits in steams or rivers.
Interestingly, only about a quarter of the diamonds that are mined on the earth get made into any sort of jewelry. In terms of diamond formation, 250 tons of ore can sometimes produce just one carat of a diamond. All the rough stones that are mined do not necessarily become diamonds.
Formation of diamonds occurs 49% of the time, typically in mines in central and southern Africa, though throughout the history of diamonds, there have been seven major places to mine diamonds: Angola, Australia, Botswana, Namibia, Russia, South Africa and Zaire.
Natural colored diamond formation occurs when there is an imperfection in the crystal structure or the chemical makeup. A common cause for blue colored diamond formation is nitrogen atoms replacing carbon atoms.
Of course, natural diamond formation is not the only method. Diamond formation can also occur in a manmade fashion. Diamonds can be treated with radiation to change the color and then heat to maintain and keep the color change.