A doublet joins a thin layer of gemstone to a stronger backing material. Sometimes opals or other gemstones are too thin or fragile to use for jewelry in any other way. Onyx and quartz are popular choices for backing materials. Choosing the right doublet glue to join the two materials is essential. “Gem Doublet Opal Pendant” by Opals-On-Black.com is licensed under CC By 2.0

A doublet joins a thin layer of gemstone to a stronger backing material. Sometimes opals or other gemstones are too thin or fragile to use for jewelry in any other way. Black onyx and quartz are popular choices for backing materials. Choosing the right doublet glue to join the two materials is essential. “Gem Doublet Opal Pendant” by Opals-On-Black.com is licensed under CC By 2.0

Question

Does anyone have any experience with making doublets?  More specifically, can anyone recommend a doublet glue? I recently tried to utilize a spare piece of hydrothermal synthetic emerald by Morion. It was too shallow to permit a full pavilion so I decided to experiment. I attached a piece of hydrothermal synthetic green quartz to the emerald to make a doublet. I used super glue to do the fixing. (I avoid using epoxy as doublet glue due to the inevitable presence of air bubbles). I made sure the two interface surfaces were true and well polished before gluing. All went well, until I polished the final facet of the pavilion. At that time, the two pieces parted company. The quartz culet fell away.

Can anyone advise on the best doublet glue to use and how to go about applying it? I only cut stones for my own satisfaction. I have no sinister motives of passing such stones on to the public. Any response will be appreciated.

Kind regards,

Keith Tucker, Ilkley, U.K.

Using Epoxy For Doublet Glue

If you want a good air-free bond, use slow-curing (24-hour) epoxy. Mount the joint in a vice padded with some cloth or newspaper.

Hope this helps,

Jim V.H.

Clean The Gemstones Before Using Doublet Glue

I use wax primarily, except for heat sensitive stones such as opal. Perhaps your stones were not properly cleaned prior to re-dopping.  Clean with alcohol and don’t touch the cleaned portion.  When I knock a stone off, I just reposition it in the transfer fixture. Then, I realign it as closely as possible using the wax left on the stone and the dop as a guide. I might add that getting it back on perfectly is extremely rare.

Best of luck,

Dennis