Emerald Oiling

Earlier this year, we had an opportunity to buy a few loose Colombian emeralds from an old dealer parcel tucked away since the late 1970s or early 1980s.  Needless to say, we jumped at the chance!

The stones we bought have that characteristic Colombian glow, with inclusions suggesting a possible Muzo mine origin (we cannot say with certainty, however).  Since this was an old parcel, the oiling treatment that is so standard for emeralds (even done right at the mine) had leaked out.  Oiling is a great treatment for exactly this reason -- it enhances the beauty of the stone, is accepted as near-universal in the marketplace, and is 100% reversible if you want to restore the original look of the stone.

We decided it would be fun to show you before-and-after photos as we lightly oiled one of these emeralds.  We selected a 3.63 carat 9.0x8.9 mm square emerald cut stone.  For comparison, here is a before picture:


We then soaked the oil in 100% pure cedarwood oil and monitored its progress as it soaked overnight (under mild pressure).  Some initial results were visible even after just 10 minutes:


And after two hours, most of the improvement there was to be seen in the emerald had already set in.  We let it soak overnight before removing it from the oil.  Then we let it rest, still covered with oil, for another eight hours, before finally using a soft cloth to gently rub away the remaining surface oil.  We did this quickly to avoid wicking.

Then we sent the stone off to be set in a lovely size 6 halo ring setting we had selected just for this emerald, in 18kt yellow gold with VS+ clarity, G-H color diamond melee totally 0.275 carats.  Emeralds are notoriously hard to photograph, and perhaps one of the worst pictures I took of the ring is the one that most accurately captures the color and glow of the stone:


This lovely ring is currently for sale in our marketplace.  To check out the product listing, just click the photo below!


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