Black natural diamonds are diamonds that have been naturally formed with a black color. These diamonds are formed in the earth's mantle, where they are subjected to high pressure and temperature conditions. The black color of these diamonds is caused by impurities of graphite or other minerals, which are incorporated into the diamond crystal structure as it forms.

Black natural diamonds are quite rare, and they are often used as gemstones in jewelry. They are prized for their unique color and for the fact that they are natural diamonds. Black diamonds are also sometimes referred to as "carbonado" diamonds, which is a Portuguese word meaning "charcoal diamond."

One of the most interesting properties of black natural diamonds is that they are incredibly hard and durable. Diamonds are known for being the hardest natural substance on earth, and black natural diamonds are no exception. They are resistant to scratching, chipping, and breaking, which makes them perfect for use in jewelry.

Black natural diamonds are also very popular in the world of fashion and style. They are often used as accents in jewelry designs, and they can be found in a variety of different styles, including earrings, rings, necklaces, and bracelets. Black diamonds are often paired with white diamonds or other gemstones to create a striking contrast.

There are a few different ways to determine the quality of a black natural diamond. One of the most important factors is the clarity of the diamond. Black diamonds are often less clear than white diamonds, which means that they may have inclusions or other imperfections that are visible to the naked eye. The fewer inclusions a black diamond has, the higher its quality and value will be.

Another factor that affects the quality of a black natural diamond is its cut. The cut of a diamond refers to the way that the diamond has been shaped and polished. A well-cut black diamond will have a beautiful sparkle and will be more valuable than a poorly cut diamond.

The size of a black natural diamond is also an important factor to consider when determining its quality and value. Larger diamonds are generally more valuable than smaller diamonds, but the size of the diamond alone is not the only factor that determines its value. The color, clarity, and cut of the diamond are all important factors to consider as well.

In conclusion, black natural diamonds are a unique and beautiful gemstone that are prized for their rarity, durability, and unique color. These diamonds are often used in jewelry and are highly sought after by collectors and fashion enthusiasts. While they may not be as well-known as white diamonds, black diamonds are no less valuable or desirable.