Justin K Prim
Published in

Justin K Prim

The Art and Joy of Recutting Gemstones

A Chinese translation of this article was originally published in Jewelry World Vol. 92, November 2019

Over the past few years, the demand for well-cut gemstones has increased dramatically. Due to the large amount of commercial-quality material whose original cut was solely meant to retain weight as opposed to maximizing beauty and color, the international gem trade has seen a huge demand for recutting, not only in the American and European markets but in Asia as well. Recutting is the process of taking a poorly cut stone and turning it into a well-cut stone, and is a great way to add value to a gemstone so that you can resell it for profit.

The art of the recut is not for the faint of heart. It’s a skill that requires an experienced eye and an experienced cutting hand. The first thing a customer will ask you is “How much weight will you lose?” If you don’t have enough cutting experience to answer this question then don’t take the job. Recutting takes a lot of practice to learn the technique, to understand the various issues that come up during the recutting process, as well as seeing what your final carat yield is over the course of dozens, if not hundreds of recuts.

The recutting of this Burmese spinel improved a poorly shaped outline as well as closing the window in order to improve the color and brightness. Before 2.03ct. After 1.38ct.

The foundational skills are able to be learned. The first thing you have to do is get the cut stone on the dop in a way that is oriented correctly to lose the least amount of weight. Before you can even get to the actual cutting though, you need a plan. This is where the experience comes in. When you first look at a cut stone you need to be able to identify what problems the cut is giving the stone and if it’s possible to solve them in a reasonable way. This kind of identification takes experience so it’s best to practice on low value stones while you learn exactly how to improve a lackluster cut. If the stone belongs to a customer, they usually have an idea on what they want to change; maybe they want to close a window, fix the proportions, change the shape to something more pleasing to the eye, or change the faceting pattern in order to transmit more light and color. There are many reasons to do a recut, but there are as many times when recutting doesn’t make financial sense.

Recutting always involves a lot of math because you need to understand how much your stone is worth before the recut and how much it’s going to be worth after you lose 10–50% of the stones weight to fix its problems. If you don’t understand these numbers then don’t take work from a client. Practice on cheap stones to start to get an idea on how much weight you lose when you repolish, when you close a window, when you have to touch the girdle. You can’t responsibly accept a client’s stone if you can’t tell them (with some degree of certainty) that you can fix the problem within a certain percentage of the original weight.

Most of the excitement in recutting is figuring out how best to change the design. Sometimes the stone just needs a slight adjustment of angles and sometimes you need to completely change the shape and cutting style of the stone. The cutters knowledge comes into play a lot in this step because if you don’t know how a Step Cut can affect the color and light return of a stone versus a Portuguese Cut then you won’t have all the tools that you need at your disposable. You need to be able to judge the original facet angles and figure out how to adjust them to make better proportions as well as how to adjust angles on the fly. The original cut is probably not symmetrical, so aside from adjusting the cut style, you will have to deal with different facets at different angles. Depending on the value of the stone, it’s not always possible to cut all the angles exactly the way you’d like to. You need to be able to improvise and adjust as you go. That’s part of the fun.

By removing some of the unnecessary bulk from the pavilion of this blue-green Tourmaline, the cutter was able to adjust the angles to bring out the blue color and minimize the green color as much as possible. Before 26.02ct. After 21.78ct.

I have to admit though, the best part of recutting is when you finish the stone and compare your work to the original cut. There is nothing like it. Cutting from rough never gives you the same feeling because you never quite know what the potential of a stone is until it’s been at least preformed. With a recut, you can clearly see what the potential was for one cutter and then you get to see the upgraded potential from your own hands and skills. It’s a great feeling as an artist and it’s an even greater feeling when you sell the stone and realize that its value has increased, despite the fact that its carat weight decreased.

About the Author

Justin K Prim is an American lapidary and gemologist living and working in Bangkok, Thailand. He has studied gem cutting traditions all over the world as well as attending gemology programs at GIA and AIGS. He is currently working on a book about the worldwide history of gemstone faceting. He works as a Lapidary Instructor for the Institute of Gem Trading as well as writing articles, producing videos, and giving talks about gem cutting history. You can find him on Instagram at @justinkprim




The collected written works of Justin K Prim : Travel Adventurer / Gemologist / Musician / Author of The Secret Teachings of Gemcutting

Recommended from Medium

Misadventures in Blacksmithing

A Colored Gemstone Buyers Guide to Cut Styles

My Journey into 3-D Printing

Designing from Life Lessons Learned

Monitor your 3D printer remotely with a Raspberry Pi

How to Model Locations With Blender

Grado Single Cable Mod Guide

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store
Justin K Prim

Justin K Prim

Gentleman Lapidary / Faceting Historian / Author of The Secret Teachings of Gemcutting / www.justinkprim.com

More from Medium

Tigers vs. Jaguars? To China’s Black Market, Bones are Bones

When Cowboys Were Her Weakness

Why The Grateful Dead is the Quintessential American Band

Sweets that are just right | Highnoon’s debut album will have you asking for more of this indie…