Precision Faceting A Story Gemstone: The Faceting Process

by Mark Oros, Hashnu Stones & Gems

Introduction

Precision faceting one gemstone at a time takes both patience and dedication. Custom lapidaries want to excel at their craft. For us, making each and every gem is a work of art. After investing time and money in gem rough, design, and the best equipment, we’ll use our expertise and the finest faceting techniques to create gems that tell stories. In this article, I’ll introduce prospective clients to the terminology and stages of the custom faceting process.

Crown Jewel: An Opal Story

Sandra was passionate about opal. She saw some of my faceted opals online and contacted me. She wanted me to facet one of her favorite rough Ethiopian opal nodules. After we spoke, she sent me a link to her website. It featured a picture catalog of her outstanding collection, which included several museum-worthy opal specimens. The faceted opal wouldn’t be used in jewelry. Rather, it would be set in a prominent location in her collection cabinet.

Next, we seriously discussed the fragility of all opal rough and the possibility of the stone faulting during the faceting process. I’m very cautious about cutting other people’s stones. If a stone has structural problems, I’d rather return it than risk ruining a prized possession. After agreeing to this condition, Sandra sent me the opal. Upon receiving it, I found the opal in very stable condition and agreed to cut it. I was delighted to move on to the next chapter in her opal’s story.

Over several video calls, we talked about the nature of opals. None are exactly alike. We discussed the best gem design to showcase the natural beauty of her prized opal. It was opaque. Light return wasn’t a consideration. Since the stone wasn’t destined for traditional jewelry, we decided to cut crowns on both sides of the opal.

Since I finished the stone in the dead of winter, I waited before sending it to Sandra. Sub-zero temperatures along the mail carrier’s path could freeze the opal. When the weather turned warmer, I sent the stone. Now Sandra could return it to her collection.

The Faceting Process: An Overview

After meeting with clients, choosing the rough, selecting a design, and gathering the equipment, we reach a complex chapter in a gem’s story. Now, the rough will become a finished stone. Inspired by human desire and artistic expression, the actual gemstone faceting process will reveal the inner beauty of a natural stone.

The custom faceting process goes as follows:

Preforming

The rough stone is ground on a series of wheels or flat laps to get a basic shape called a preform. This allows the faceter to look more closely at the stone and orient it properly for dopping.

Dopping

The faceter attaches the stone to a brass dop (post) that will fit into the spindle of the faceting machine mast. The stone will now become part of the machine and won’t move until the pavilion is done.

Pavilion

The pavilion is the term used for the bottom of the stone. At this stage, the faceter completes the pavilion and girdle. The final size of the gemstone is set and ready for the crown.

Transferring

Before cutting the crown, faceters must re-dop the stone so they can finish the other side. This is called transferring the stone.

Crown

The crown, the top part of the gemstone, is cut and polished after transferring. Crown cutting will leave a point/peak of facets that will need to be cut off in the next step.

Table

Faceters now cut and polish the table, the flat top of the gemstone that allows light to enter and exit the gemstone.

Release And Clean

Next, faceters release the finished gemstone from the dop. They can heat the dop (never the stone) or use chemicals to break the glue/wax bond. Faceters now clean the stone and prepare it for shipment.

Freeform and Diagram Faceting

Custom lapidaries take years to learn gem faceting techniques and hone their skills. Of course, I simplified the faceting process for the overview.

Gem design diagrams describe cutting and polishing in a sequence of steps. However, some custom faceters will “freeform” facet based on their experience and imagination. Either kind of faceting is acceptable. The faceting process can take a few hours or dozens of hours, depending on the nature and size of the stone and the complexity of the design.

Precision Faceting A Story Gemstone: 5-Part Series

Part 1: Choosing Rough

Part 2: Gem Design

Part 3: Faceting Equipment

Part 4: The Faceting Process

Part 5: Custom Faceting Advice