**Abstract**
The market value of black diamonds has historically been overlooked, and they were often not regarded as gem-quality stones. However, with the evolution of fashion, people's preferences for colors have changed over time. Among black gems, black diamonds stand out due to their striking, mysterious black luster. Thanks to advancements in the jewelry industry, they are now widely used in elegant and retro designs. Today, black diamonds are no longer rare in terms of availability but are considered high-end collectible pieces, often found in boutique jewelry stores.
Since the early 20th century, approximately 600 tons of diamonds have been mined globally, making them a popular choice among the upper class. Among the various colored diamonds—colorless, fancy-colored, and black—each has its own charm. Colorless diamonds are clear and pure, while fancy-colored ones offer vibrant hues. Black diamonds, however, bring a unique mystique that sets them apart in the international jewelry market. Their rarity makes them especially valuable. But where do these black diamonds come from? Why are they so scarce? And what factors have led to their growing popularity?
**How Black Diamonds Are Formed**
Geologically speaking, black diamonds, like other colored diamonds, form deep within the Earth’s mantle. They are then brought to the surface through volcanic activity. These diamonds are typically opaque, with a specific gravity between 3.1 and 3.3, and they share the same 10 on the Mohs hardness scale as other diamonds. However, most black diamonds are encased in gray or dark gray materials, which cause surface imperfections such as scratches and cracks. These impurities also contribute to their opacity, making it difficult to achieve a uniform black color.
The term "black diamond" was first introduced by the Portuguese in Brazil during the mid-18th century. To date, black diamonds have only been found in Brazil and the Central African Republic. While diamonds in other regions, such as Australia, Siberia, China, and India, form under similar conditions, they are not the same as black diamonds. Recent research suggests that black diamonds may actually be remnants of a supernova explosion, arriving on Earth as large as 1 kilometer in diameter—like small planets.
**Mysterious Legends of Black Diamonds**
Throughout history, black diamonds have been surrounded by intriguing myths. In ancient India, when black diamonds appeared as twin crystals, they were believed to be the eyes of a serpent. Some legends suggest they were associated with death and even linked to the gods of ancient India. In medieval Italy, black diamonds were known as “stones of reconciliation.†It was said that if you had a disagreement with your lover, simply placing a black diamond on her face could erase all misunderstandings. Though this method might be costly, it highlights the symbolic power of black diamonds.
**The Rare Value of Black Diamonds**
Most diamonds are colorless or have a yellow, orange, or brown tint. Colored diamonds are rare, and those with intense color are even more valuable. The value of a colored diamond depends on the intensity of its hue, which is influenced by the crystal structure or the presence of impurities. A black diamond, in particular, represents a transitional state between graphite and diamond, making it one of the rarest types in the diamond family. Unlike other colored diamonds, black diamonds are not only rare but also highly sought after for their unique appearance.
It's important to distinguish real black diamonds from colorless diamonds with black inclusions. These inclusions are natural substances trapped inside the diamond during its formation, and they significantly reduce the value compared to genuine black diamonds.
**Why Black Diamonds Are Now in High Demand**
First, black is a universally appealing color that resonates with people of all ages. Second, it pairs well with other colors, offering endless design possibilities. Beyond myths, modern consumers are drawn to black diamonds for their distinct characteristics. They provide a contrast to the brilliance of gold and platinum, enhancing the visual appeal of jewelry when paired with other stones or white diamonds.
Cutting black diamonds can be challenging due to their internal flaws, but when done properly, they can achieve remarkable beauty and elegance. Rarity, combined with fashion trends, has made black diamonds highly desirable. In recent years, the retro trend—especially the Victorian style—has revived interest in black diamonds. Queen Victoria of the UK, known for wearing black jewelry to express grief, helped popularize the color in jewelry design.
Today, black diamonds are reimagined with new materials like black pearls, giving them a modern, sophisticated look. They no longer carry the somber sentiment of mourning but instead symbolize elegance and style. In many jewelry designs, black diamonds play a central role, adding mystery and sophistication. There are several famous black diamond pieces around the world that have become iconic in the jewelry industry, each with its own unique story and allure.
Grinding Stone
Industrial applications editor broadcast
Whetstone sintered corundum (ruby) : A kind of microcrystalline corundum product sintered at high temperature. It has a compact and delicate structure and high hardness and strength.
The products are rosy red. The products are small grinding wheel type whetstone, standard type whetstone and grinding head type whetstone. When grinding the workpiece, it can maintain sharp edge and stable geometry for a long time.
It is suitable for forming and grinding of instrument industry, precision parts, micro cutting tools, tools and precision abrasive tools, etc. The precision surface roughness of machining can reach about 0.05μm.
Product SPECIFICATIONS: flat sand wheel whetstone with diameter less than 100 for small grinding wheel type, whetstone with various geometric shapes less than 200*50*25 for standard type, whetstone with diameter less than 25 for grinding head type.
Grinding method
About diamond grinding paste, particle size from W40 to W0.5. W40 is the coarsest, with a large amount of grinding, and W0.5 is the smallest. It is used for polishing, and it does not anneal, and it can also grind the hard knife.
Method of use:
The coarse W40 abrasive paste applied to borotartar can accelerate and increase the grinding amount without annealing.
Then, AFTER the rough grinding paste on the knife is cleaned, W0.5 grinding paste is applied to the ruby or natural jade for polishing, and the effect thrown out is a mirror.
Green silicon carbide, white corundum, brown corundum of these three kinds of whetstone hardness is not enough, coupled with a little coarse particle size, easy to grind out the cross, and the other three kinds of whetstone in polishing, grinding will not annealing.
If the particle size is greater than 1000, there is no difference. It mainly depends on the grinding paste used. When the grinding paste of W1.5 is applied to the ruby with 1000 mesh, its grinding effect is the effect of the grinding paste of W1.5, that is, the effect of the whetstone with 2500 particle size
Grinding Stone,Diamond Grinding Pellets,Carborundum Oil Stone,Oilstone Sharpening Stone
Henan Jinlun Superhard Material Co., Ltd , https://www.jinlunsuperhard.com