Diamonds are cut into many different shapes and sizes, and each cut has its own specifications. They all reflect light in different ways, giving diamonds their unique brilliance. The diamonds you see at the jewelry store have all gone through a cutting and shaping process. They start off as rough stones, and experts transform them into radiant, faceted gems. Diamond cutting is a difficult job. It requires specialized knowledge and techniques. It also calls for the right tools and equipment and can be a long process. There are five steps in the diamond-cutting process. Here is everything you need to know about how diamonds are cut.
Finished diamonds start off as rough, or uncut, stones. They resemble lumps of glass. However, with the right planning, a rough diamond can be cut and made into one or more brilliant, valuable diamonds.
Diamonds are first analyzed from an economic perspective. Manufacturers need to consider the maximum return on their investments and how quickly they can sell the finished diamond.
Special devices scan rough stones to get three-dimensional models. Inclusions taken from photographs are also placed on the model. After inspecting the model, the best cuts for the stone can be determined.
Cutting the Diamond Down to Size
After the planning stage is complete, cutting the diamond down to a manageable size is next. To separate and make the stone the desired size, the cutter needs to either cleave or saw the diamond:
- Cleaving: Cleaving is the splitting of the diamond along its natural line. A wax or cement mold holds the diamond in place so a groove can be made.
The groove is carved along the weakest part of the diamond known as the tetrahedral plane. Afterward, a steel blade is placed in the groove and is struck to cut the diamond in two.
- Sawing: Sawing is necessary when there is no weak plane where the diamond needs to be cut.
In these cases, cutters can use a phosphor-bronze blade to saw. The blade rotates and can cut through the diamond to get it down to a manageable size. A laser can also be used to saw the diamonds into separate pieces.
Giving Diamonds Their Shape
After a diamond has been cleaved or sawed, it can then be shaped. Diamonds can be cut by hand or by machine. There are two cutting techniques that are used to give diamonds their shape:
- Bruting: Bruting refers to cutting diamonds by hand. Cutters use the hardness of diamonds to cut other diamonds. A special stick-like tool is used to hold the diamond in a bowl of cement. With one corner exposed, the cutter can rub diamond parts against each other to brut them. The cutter rotates the diamond until each corner is bruted.
- Cutting: Cutting refers to cutting diamonds via a mechanical process. A diamond is first put in a lathe where it rotates while another diamond rubs against it to create the desired shape.
A diamond’s cut refers to the stone’s proportions and ability to reflect light. The round brilliant cut is the most popular, but there are plenty of shapes and sizes that can match just about any distinct style preference. Here are some popular diamond cuts:
- Round brilliant cut: the classic round-shaped diamond.
- Cushion cut: also called pillow cut, is a square or rectangular shape with slightly rounded corners and sides.
- Princess cut: a square or rectangular cut.
- Emerald cut: a rectangular cut with rectangular facets.
Polishing the Diamond
After planning, cleaving and bruting, the diamond is ready to be polished.
For a diamond to be polished, it needs to sit on an arm above a rotating wheel that is covered in an abrasive diamond powder. The rotating wheel smooths the diamond’s surface and polishes the stone, resulting in a smooth, finished look.
Polishing is an important step to the process. Poor polishing masks a diamond’s light return. However, an excellent polish job results in an extremely smooth surface, which allows for more brilliance, fire and scintillation on a diamond.
The Final Inspection
The diamond is now ready to go through the final step. It is thoroughly cleaned in acids and then goes through careful examination to make sure that it meets the manufacturer’s expectations and standards.
A grading facility then grades the diamond for a final review. The diamond is checked for carat weight, color, clarity and cut. Diamond cutting is a difficult process. A lot of work goes into transforming a rough stone into a brilliant, finished diamond.
Mark’s Diamonds represents one of the largest manufacturers in the world, giving us access to nearly limitless selection of diamonds. Shop our international diamond inventory at marksdiamonds.com.