Dopping wax for lapidary: how to use it? Materials, steps, and alternatives
- Oscar Bautista
- Sep 5
- 7 min read
As an experienced gem cutter, I can tell you that one of the most delicate moments during the cutting process is the gemstone dopping (when you attach the gem to the dop):
You need precision and a steady hand to ensure that the stone is properly centered and, as a result, you get the desired results.
So, if you are venturing into the world of gem cutting as a hobby or business and want to develop a good gemstone dopping technique using wax, I invite you to continue reading.
Based on my experience, I have created this guide in which you will discover:
What materials are needed to attach a gemstone to the dop?
Well, before you learn how to attach the gemstone to the dop, you need to know what materials you will need:
1. Wooden or metal dops for polishing and faceting
You can find wooden and metal (aluminum or brass) dops on the market. I always use brass ones, but either material works quite well.
In terms of size, you will find that there are thick and thin dops in a wide variety of diameters.
You can use the thin ones to cut small gemstones and the thick ones for larger ones. Just make sure the diameter is compatible with the faceting machine you are using.
The finish on one end can also vary: there are flat, concave, and pointed dops.
You can use flat dops to glue the crown and facet the pavilion, and concave dops to glue the pavilion and facet the crown. However, in my opinion, the shape of the dop is not such a decisive factor.
I say this because I have been using pointed-end dops for over 30 years, and I dare say that the result depends on how well you use the wax to cover the end of the dop and glue the gemstone.
The decision is up to you. My suggestion? Try different shapes and sizes, and choose the types of dops that best suit your needs and cutting style.
2. Dopping wax
Many gem cutters use sealing wax to attach gemstones to dops because it’s safe, economical, and long-lasting: if you use it correctly, you will find that you can reuse it over and over again.
It is also a very versatile material. By applying heat, you can shape it as needed, while increasing or decreasing the amount on the dop and the stone.
You can find green, red, brown, and black dop waxes on the market, but I recommend green and red waxes the most.
Now, what is the difference between the green and the red dopping wax?
Green dopping wax: This is a low-temperature wax that melts at approximately 65°C (150°F). It’s ideal if you are going to cut heat-sensitive gemstones such as turquoise, opal, and labradorite.
Red dopping wax: This is a general-purpose wax that melts at approximately 70°C (160°F) and has a high holding power. You can use it on a wide variety of gems, including beryls, corundums, and quartzes.
As you can see, both types of wax can be used to attach gemstones to the dop, but you should use the green dopping wax if you are cutting gemstones that are highly sensitive to heat.
3. Alcohol lamp or burner
The alcohol lamp, also known as a burner, has two functions in the gemstone cutting process:
Melting the wax to attach it to the dop.
Heating the gem to adhere it to the wax and, consequently, to the dop.
You must use the alcohol lamp carefully and in a controlled manner to prevent the gem from breaking or changing color, or bubbles from appearing in the wax and burning (if it burns, it can no longer be used).
My suggestion is to use a small alcohol lamp, such as those used in laboratories.
4. Centering device, aligner, or transfer jig
Regardless of the name, these accessories are used for the same purpose: to keep the gemstone centered in relation to the dop and prevent the facets from becoming misaligned.
In this image, you can see the centering device. For it to work properly, you must use it as soon as you glue the gem to the dop, while the dopping wax is still warm.
The transfer jig is used to move the gem from one dop to another.
In other words, you use one dop to cut the pavilion, and then transfer the stone to another dop to cut the crown, which is the top part.
Now that you have the list of materials you need to use, learn the steps you must follow to dop the gemstones using wax.
How to dop a gemstone using dopping wax?
Based on my experience, I can tell you that these are the steps you should follow to dop gemstones using dopping wax:
Make sure that the alcohol lamp has enough alcohol to work.
Light the alcohol lamp.
Hold the wax stick (dopping wax) by one end and bring the other end close to the flame so that it begins to heat up.
When the wax is hot, spread it on the dop (the amount will depend on the size of the dop and the stone).
Bring the gem close to the flame for a few seconds and gently (do not overdo it because you can damage the stone).
Quickly heat the wax on the dop and bring it close to the stone so that the two stick together.
If necessary, heat the wax stick and add more to the dop to ensure a better hold.
Use your fingers to shape the wax and improve the bond between the dop and the stone.
Before the wax cools completely, place the dop in the centering tool or transfer jig to ensure that the gem is centered and aligned.
To remove the gemstone from the wax, you can use a little heat and a scalpel or cutter. To remove any excess wax without damaging the stone, you can use alcohol.
Alternatives to dop wax: gemstone dopping techniques using epoxy and Super Glue
Many gemcutters use epoxy resin and instant glues such as Super Glue to attach gemstones to the dop.
Find out below how both methods work, their advantages and disadvantages.
How to dop a gemstone using epoxy?
Dopping gemstones with epoxy resin is a reliable method and is ideal for gems that will be subjected to considerable pressure during cutting.
Here are the steps you need to follow:
Clean the stone and the tip of the dop with alcohol or acetone to remove any oil, dust, or dirt residue, thus ensuring good adhesion.
Using an alcohol lamp or a dop station, gently heat the stone and the dop so that the resin flows better and the bond is stronger. Avoid excessive heat for sensitive stones such as opal.
Prepare the two-part epoxy resin (resin and hardener) according to the manufacturer's instructions. Generally, you should mix equal amounts of both components until the color is uniform. You have to do this quickly, before the resin starts to cure.
Apply a small amount of the epoxy mixture to the tip of the dop so that the base of the stone is covered but does not overflow on the sides.
Using tweezers, place the stone on the epoxy in the dop and press gently. Make sure it’s perfectly aligned and centered according to the desired cutting axis.
Allow the resin to cure completely (the time depends on the type of epoxy you are using). In the meantime, keep the dop in an upright position so that the gem does not move.
In general, I can tell you that the main advantage of using epoxy for gemstone dopping is its adhesive strength:
This component creates a strong, durable bond that can withstand the heat and movements of the faceting process, reducing the risk of the stone coming loose.
However, its disadvantage is the preparation and curing time, which is longer compared to other adhesives such as dopping wax and Super Glue.
In addition, it requires heat both to glue and to remove the stone from the dop, which can be a risk for gems that are sensitive to high temperatures such as opal (especially if you don't have enough experience yet).
How to dop a gemstone using Super Glue (Cyanoacrylate)?
Super glue is another effective alternative, and is especially useful if you are going to cut smaller gems or if you need a quicker solution.
Here are the steps I recommend following if you want to use it in your gem cutting process:
Clean the stone and the dop with alcohol or acetone to remove any impurities that could affect the bond between them.
Optional: lightly scratch the surface of the dop with fine sandpaper to create a texture that improves the grip of the glue. This is done by some gem cutters to increase adhesion.
Apply a small drop of good quality super glue to the tip of the dop. If you prefer, you can use gel glue, as it’s easier to control.
Place the stone on the drop of glue and press firmly for a few seconds. You have little time to align it correctly before the glue begins to set.
Apply a small amount of cyanoacrylate accelerator around the base of the joint (this step is optional and helps the glue cure faster).
Although this type of glue sets in seconds, I suggest you wait a few minutes before you start cutting. This will ensure that the gemstone-dop bond has reached its maximum strength.
As you can see, fast (almost instantaneous) bonding is the biggest advantage of using an adhesive such as Super Glue to attach gemstones to the dop.
Furthermore, as it doesn’t require heat for application, this makes it a safer alternative if you are going to cut gemstones that are very sensitive to temperature.
However, this method has one disadvantage: the gem-dop bond is not as strong or as resistant as the one achieved when using dopping wax or epoxy.
For this reason, there is an increased risk of the stone coming loose due to movement or heat generated during the cutting process.
So, what is the best method for dopping gemstones?
There is no definitive answer because it all depends on the type of gemstone, your skills with each of the adhesives/glues, and your preferences.
My recommendation is that you try out these three techniques and decide which one best suits your gem cutting style.
