The diamond, from a rare mineral to a precious and symbolic stone
“A diamond is forever”, says a famous slogan. The phrase, conceived in 1947 by De Beers, the world's largest diamond mining company, sums up in a few words all the meanings that have been attributed to this stone since then. The Diamond, in fact, it is one of the most used stones for jewels, especially for those that symbolize eternal love, such as thering with solitaire, the most classic engagement gift.
Not everyone knows, however, what is the origin of this stone and why it is so precious.
Where do diamonds come from
Il Diamond it is a mineral composed entirely of carbon, the chemical element at the base of all forms of life. As explains the Gemological Institute of America, the world's most authoritative organization for the evaluation and certification of diamonds, its origin dates back more than a billion years. In fact, it was created in the earth's mantle, more than 200 kilometers below the surface, where the very high temperatures of over 1000 °C and the very strong pressure (about 45.000 times higher than that at sea level) made the carbon atoms. Thus crystals were formed which gave rise to diamonds.
For hundreds of millions of years these crystals have remained within the earth's mantle. It was the activity of ancient volcanoes that brought them to the uppermost layers of the earth, inside a rock called kimberlite. Most diamonds are mined deposits of kimberlite, which are called primary deposits. The erosion of kimberlite can release rough stones, which the water then transports, creating so-called secondary deposits.
The first extraction from the rock dates back to 1869, when a kimberlite mine was discovered in South Africa. Today among the main diamond producing countries are Botswana, Russia, Angola, Canada, Congo and Brazil.
A hard, tenacious, resistant mineral
One of the best known properties of the Diamond is its hardness: it is in fact the hardest natural mineral in the world. This is attested by the Mohs scale, which takes its name from the mineralogy expert who devised it in 1812 and which establishes ten degrees of hardness of minerals. The scale goes from minerals defined as soft, such as talc and gypsum, which can be scratched with a fingernail, to the hardest, which is precisely the Diamond, which can scratch any other natural substance, but can only be scratched by another diamond. For this reason, the Diamond it is also used in industry, to make tools for cutting, drilling and polishing other materials.
Il Diamond it is also a tenacious material, i.e. capable of undergoing shocks without breaking, and is very resistant to heat. A diamond can remain unchanged up to a temperature of around 1500°C.
The ideal stone for a precious jewel
The origins of the Diamond and the complexity of its extraction from kimberlite make it one of the rarest and most precious stones in the world. There are different types: from the traditional one, appreciated for its brilliance, to the colored ones, up to the black Diamond, very rare and difficult to work. Their value is not unique, but changes according to the characteristics of the stone.
The elements that establish the value of a diamond they are the so-called 4 C, from the initials of the English terms:
- color
- clarity
- cut
- carat (carat)
Summarizing, we can say that a Diamond it is all the more precious the more it is colorless and transparent, without any impurities, with a precise and accurate cut and naturally of a high number of carats, which express the weight of the stone.
However, the 4 Cs deserve to be known in more detail, because they are the characteristics that allow a diamond to be accurately evaluated. We will therefore talk about it in a future article.