The diamond – king of precious stones
The name “diamond” itself reveals something about its most well-known property: the Greek word adámas was used in ancient times for particularly stable and hard materials. Even famous writers such as Plato wrote about the robustness and beauty of diamonds.
These precious stones were formed billions of years ago from carbon, which was pressed into diamonds in the earth through heat and pressure. They came to the earth's surface through volcanic eruptions and have since been traded as the most valuable gemstones in the world.
Diamonds: gemstones, talismans, tools
But long before diamonds were traded worldwide as precious stones, they were used by the Indians as talismans. The Romans also attributed special abilities to the stones and used diamonds as tools for the first time.
Meanwhile, boron – the technical term for industrial diamonds – is mainly used for drilling and cutting tools. For example, construction workers can cut asphalt with the help of diamond tools.
Diamond powder is also frequently used in industry as an abrasive or sawing powder. In private households, diamond abrasive grain is excellent for sharpening knives.
Artificial diamonds
Since the mid-1950s, diamonds have been produced artificially. In this process, graphite is pressed into a diamond at extreme heat and high pressure. It takes several weeks for the graphite to become a diamond, even if a catalyst is used to accelerate the process.
The artificial diamonds are mainly produced for use in industry. For jewelry production, cubic zirconia is used instead of synthetic diamonds – artificially produced zircons. End users do not recognize any difference and cubic zirconia is significantly cheaper to produce.
The value of diamonds
Not every diamond has the same value. If you want to buy diamonds, you should first look at the most important value determination criteria for these special gemstones.
The value of a diamond is determined by the 4 C's:
1. colour: diamonds are colorless in their pure form. However, impurities or defective crystal structures can lead to discoloration. This naturally affects the value of the gemstones.
2. Clarity: The clarity of the diamonds is determined by experts using a magnifying glass with 10x magnification. The gemstone is carefully examined for inclusions inside the stone and surface defects.
3. Cut: Two criteria are important for the cut – shape and proportions. If the stone has been cut into a perfect brilliant cut, for example, this increases its value. When considering the proportions of the stone, attention is paid to the symmetry of the facets or different size ratios, among other things.
4. Carat (Weight): The weight of diamonds is measured in carats. One carat is equal to 0.2 grams.
Use
Diamonds are used in almost all of the most valuable pieces of jewelry in the world. The currently most valuable diamond is the blue “Hope Diamond” with an estimated value of around 250 million euros. The Hope Diamond was even owned by the Sun King, Louis XIV. Today, the necklace can be admired in the Smithsonian Museum in Washington, D.C.
A famous piece of modern diamond jewelry was worn around the neck of actress Audrey Hepburn. The “Tiffany Diamond” comes from one of the oldest South African diamond mines – the Kimberley mine. The yellow diamond was only worn twice: once by the wife of an American graduate at a Tiffany ball and the second time by Audrey Hepburn for the photos of the film “Breakfast at Tiffany's”.
Diamonds can be worn as an ensemble or individually. Depending on the color, the stones can be combined with white gold or even gold-colored chains. Whether a pear-shaped stone on a white gold chain or a red diamond on a gold bracelet – the diamond is one of the most versatile precious stones.
The American Gem Society names the diamond as the birthstone for the month of April. The precious stone stands for strength, stability and eternal love. It is therefore only logical that many couples buy diamonds to have them incorporated into engagement or wedding rings.
Origin & mining sites
The first diamond finds date back to the 4th century BC in India. It was not until almost 1,000 years later that the first diamonds were found in Indonesia – more precisely in Borneo. In the 18th century, a Portuguese man in Brazil came across a diamond by chance, whereupon the search for diamonds began worldwide.
The first diamond in Africa was discovered in 1769, and South Africa became the main supplier of the precious stones. In addition to South Africa, diamond mining is still practiced today in Botswana, Angola and Namibia.
The first diamond in Russia was discovered in 1826. Since then, Russian mines – extinct volcanoes – have been mined for diamonds. Meanwhile, Russia has become the main supplier of diamonds due to its extensive diamond mining.
Properties
Diamonds are a type of mineral and are usually colorless. However, discoloration can occur due to contamination by trace elements or disturbances in the crystal lattice. This is why diamonds can be colored green, yellow, blue, red or, in some cases, black.
Diamonds are the only precious stones to achieve a 10 on the Mohs hardness scale. Rubies achieve a 9 on the Mohs hardness scale, but are many times “softer” than diamonds, since the scale is not linear.
Inclusions and flaws
Diamond purity is one of the criteria used to determine its value. There is no such thing as a diamond without inclusions or blemishes. Inclusions are found in the stone and are caused, for example, by foreign bodies or cracks inside the stone. They can be gaseous, liquid or solid.
Flaws affect the surface of the gemstone and are caused, for example, by mining or wear and tear (in the case of gemstones). To determine the value of diamonds, the size, number, coloration, location, orientation and visibility of inclusions and flaws are crucial.
Diamonds are considered “pure” when an expert cannot detect any inclusions or flaws with a 10x magnifying glass.
Treatment
Due to their rarity, “pure” diamonds are very valuable. In order to improve the appearance and value of lower-quality stones, there are various methods for treating them.
For example, diamonds with discolorations are heated to ultra-high temperatures and exposed to high pressure. This compresses the crystal lattices that form molecules and atoms, making the stone clearer and brighter.
The purity of the diamonds can also be improved. A laser drill is used to burn small inclusions. Colorless liquids such as oil or resin are used to close small cracks or holes.
Incidentally, untreated and uncut diamonds are known as “rough diamonds”.
The brilliant cut is what makes diamonds so valuable
The typical brilliant cut of a diamond was developed at the beginning of the 20th century. The word “brilliant” is often used as a synonym for any diamond, but this is only the case if the diamond has actually been given a brilliant cut.
This particular type of cut is precisely defined:
- At the crown: 1 table facet, 8 table facets, 8 main facets, 16 girdle facets
- At the pavilion: 1 culet, 8 main facets, 16 girdle facets
- Cut: round
The culet is not always present and the pavilion can also be pointed.
If the facets are exactly symmetrical and correspond to the optimal proportions, most of the light in the stone is reflected and some of it is even refracted. This makes the stone particularly sparkling – hence the name brilliant (French = shiny/sparkling).
It is this perfect cut that gives the diamond its value. Of course, a flawless diamond is already very valuable, but a perfect brilliant costs significantly more than a differently cut diamond.
