What Is Used To Cut Diamonds?

Diamond is one of the hardest substances existing on the earth. As you know from our blog and video on “Can You Break a Diamond,” diamonds are not impervious to breakage. So, what’s up with the “hardest substance” definition?

With Diamonds, Hardness Refers to Scratch-Resistance

In other words, there is no other earth-bound, naturally occurring material that can scratch a diamond without hard force. (Mineralogy nerds and the intellectually curious: please read this article if you want to learn about the two substances that are technically harder than diamond!) 

So, diamonds stay sparkling for a long time because they are not readily scratched. But thankfully, they can be cut into the beautiful gems loved for centuries.

Diamonds are difficult to cut and diamond cutting requires particular expertise and tools. Nevertheless, diamonds are cut with great care, excellence, and expertise. This is because it is an extremely valuable and exquisite object that requires the highest cutting quality–precise and particular..

How Do We Cut Diamonds?

 Image Courtesy of KBK Group

Lasers are Used to Divide or Facet Diamonds

Today, diamonds are cut mainly with lasers. This is due to the high precision that lasers offer when cutting diamonds. They can easily cut diamonds in a way that enhances their brilliance and beauty without damaging them. Additionally, lasers are quite useful in cutting diamonds that have structural irregularities that would make more mechanical methods difficult.

Rotary Saws Charged with Diamond Dust

This method is used to divide well-formed diamond rough into forms suitable for faceting. The conventional diamond saw is a metal-alloy disc at 2 to 2.75 inches in diameter, spinning at about 3,000 to 8,000 revolutions per minute. These saws are usually mounted in rows, and controlled by a sawyer or computer so many stones are cut simultaneously. 

A metal roller is used to charge the saw blade with a paste of diamond dust and olive oil. After the sawing commences, the blade is continuously charged with dust removed from the stone itself.

We Use One Diamond to Shape Another Diamond

Image Courtesy of Cape Town Diamond Museum

 The girdle of the diamond is the edge of the diamond’s widest part. It is a unique part of a diamond because it defines its outline, as opposed to producing brilliance. Girdles are therefore cut using a technique unique to them. In fact, the method of shaping a diamond’s girdle is called by unique names: bruting, rounding up, or girdling. One method of bruting is using the point of one diamond to carefully carve another diamond’s girdle into its final shape.

Diamond Girdle Saws are Used to Shape Diamonds

Another way to shape the girdle of the diamond is to use a girdle saw. This diamond-cutting process involves using a thin and flexible diamond blade, which glides over the surface of the diamond to ensure that it cuts smoothly and cleanly, and into the shape that’s wanted.

Ancient-to-Modern Water Jet Method of Bruting Diamonds

Yet another way to define the final outline of a diamond is to use a water jet. Water jet cutting is actually an ancient method that has been refined over centuries. It involves using high-pressure water streams to divide diamonds, which can either be submerged or above the water.

How Do We Facet Diamonds

Due to diamonds’ extreme hardness, faceting and polishing occur simultaneously (unlike with colored gems, which is a two-step process). Diamonds are faceted/polished on a large, horizontal, cast-iron disk called a scaife, which rotates at about 3,000 revolutions per minute. 

What Does Olive Oil Have to Do with Diamond Cutting?

Like diamond saws, scaifes are charged with diamond dust in olive oil. Tiny grooves in the surface of the scaife hold the mixture so it is not spun off by centrifugal force.

Diamond Cutting Uses Machinery Uniquely Adapted for the Task

The diamond to be polished is mounted in either a traditional or mechanical dop. Dops are essentially small cups in which the stone is held by a substance such as lead. Mechanical dops are used in the cutting of most diamonds; but the finest and largest diamonds are generally held in a handmade traditional dop. 

The bruted, but otherwise unfaceted diamond is mounted in the dop, and the dop is held against the scaife at a different angle and position for each and every facet. This process entails a great deal of care and excellence. 

Bottom Line of Cutting Diamonds

The procedures, equipment, and tools involved in cutting diamonds are unique, and therefore only highly skilled professionals can cut fine diamonds. This is because the process entails both technical expertise, and a great deal of care. It is important to note that all the procedures used in cutting diamonds should be properly performed in order for you to have high-quality, perfect, and beautiful cuts. 

The Diamond Wizard is Our Diamond Cutter

Known throughout the industry as “The Diamond Wizard,” Maarten de Witte is Alara’s diamond cutter. In addition to repairing and recutting chipped and broken diamonds for our customers, Maarten has developed a number of unique diamond cuts. His signature cut, the American Rose Brilliant, combines two traditional styles, by having the artistry of a classic rose-cut crown combined with the precision of a highly reflective modern pavilion. This cut is an Alara treasure, and we are always on the lookout for appropriate pre-conflict diamonds that can be cut into one of these! 

All of Maarten’s diamonds are sourced, designed, and cut exclusively in the USA. We are proud to be your access point to Maarten’s work.

To learn more about diamond cutting, contact us today at  Alara Jewelry.