Rough diamonds and natural diamonds are closely related, but are fundamentally different in terms of properties and value propositions.
What are natural diamonds?
The formation conditions of natural diamonds are very harsh, and most diamonds are formed under high temperature and pressure in the geology. The pressure of diamond formation conditions is 4.5 to 6Gpa, and the temperature is 1100 to 1500°C. Roughly converted, it is equivalent to a depth of 150 to 200km underground. There are only a few places deep in the earth that have the physical and chemical conditions for the formation of such diamonds. From the diamond mines currently mined, it has been found that the vast majority of diamonds were formed between 2 billion and 3 billion years ago. Some diamonds found in South Africa are even as old as about 4.5 billion years, which also confirms that diamonds are on earth. It began to crystallize inside the earth shortly after its birth.
What is a rough diamond?
Artificial rough diamonds are diamonds created by simulating the natural environment. There are two common production methods.
CVD diamond rough: CVD chemical vapor deposition method: thin wafers of diamonds are needed as seeds, and then placed in the cultivation chamber, and given certain conditions, the diamond wafers are stacked layer by layer to become a rough cultivated diamond.
HPHT diamond rough: HPHT high temperature and high pressure method: directly simulates the formation conditions of natural diamonds in the earth’s mantle, and gives carbon atoms high temperature and high pressure in the growth chamber to grow into diamond crystals.
Here’s a detailed comparison:
1. Differences in appearance of diamonds:
Rough Diamonds: As the name suggests, rough diamonds are uncut and unpolished gemstones found in nature. They often have irregular shapes, varying sizes, and often have a dull outer surface due to the presence of impurities and surface defects.
Natural Diamonds: Natural diamonds are cut and polished to give them their characteristic luster, fire, and sparkle that make them so popular. They come in a variety of shapes, including round, princess, cushion, and more, depending on the cut.
2. Formation method:
Rough Diamonds: Rough diamonds are formed deep in the Earth’s mantle through millions to billions of years of high temperatures and pressures, and are formed from carbon atoms arranged in a crystal lattice structure.
Natural Diamonds: They are essentially rough diamonds that have been cut and polished to reveal their inherent beauty and maximize their light-reflective properties.
3. Diamond value:
Rough Diamond: The value of a rough diamond mainly depends on factors such as its carat weight, clarity, color and shape. Rough diamonds are usually sold to diamond manufacturers and traders through specialized channels.
Natural Diamonds: Once cut and polished, natural diamonds command significantly higher prices for their aesthetic appeal and suitability for use in jewelry. The value of a natural diamond is affected by the famous 4Cs (carat weight, cut, clarity and color) as well as other factors such as fluorescence and symmetry.
4. Diamond treatment methods:
Rough Diamonds: Once mined, rough diamonds undergo a series of processes including sorting, planning, cutting or sawing, rough grinding, polishing and final inspection to transform them into polished diamonds.
Natural Diamonds: Polished diamonds are cut and faceted by skilled craftsmen to enhance their brilliance and beauty. The cutting process involves precise calculations to maximize the diamond’s optical properties while minimizing waste.
5. Application scenarios:
Rough Diamonds: While rough diamonds are primarily used in the diamond industry for cutting and polishing, they are also used in industrial processes due to their exceptional hardness.
Natural Diamonds: Polished diamonds are primarily used in jewelry, including engagement rings, earrings, necklaces, and bracelets. They are also used in a variety of industrial applications such as cutting tools, abrasives and high-pressure research equipment.