Clarity enhancement in opals?

[jordyonbass]

Mystery solved! Is this a common treatment, in your experience?

It's not very common but it is accepted as a form of treatment, this is kind of a last ditch attempt to save an Opal with great looking colour but has more cracks and fissures than an active volcano erupting.

As a cutter, if one of my Opals were showing cracks and other issues like that which needed to be filled with resin then it would be past the point of no return for my stock standards. That stone would never see a proper cut and polish.

 

[CircularBrilliant]

It's not very common but it is accepted as a form of treatment, this is kind of a last ditch attempt to save an Opal with great looking colour but has more cracks and fissures than an active volcano erupting.

As a cutter, if one of my Opals were showing cracks and other issues like that which needed to be filled with resin then it would be past the point of no return for my stock standards. That stone would never see a proper cut and polish.

Good to know, and I really appreciate you hunting down the answer on what was done to the stone. Definitely confirms this is a hard pass!

 

[fredflintstone]

So it looks like @arkieb1 was on the money here, this Opal has had fissure and cracks filled with a resin to help stablize the stone and it's crazing. GIA have explained that they label this treatment as clarity enhancement for Opal, which doesn't really do much to help buyers discern exactly what has happened to an Opal. I wouldn't regard filling an Opal with resin to stablize it as a clarity enhancement since it does little to nothing to actually change overall clarity.

True and some Opals it does not work at all.

 

[jordyonbass]

True and some Opals it does not work at all.

I'm pretty sure that those kinds of treatments pretty much won't work in stable material with low water content like LR Black Opal. No way for the resin to permeate into those cracks and fissures. Some of the blokes that cook Andamooka matrix have mentioned that if they put the really good gem material in to cook with the Matrix that it has little effect on the gem material.

I've partaken in an Opal cook once, was way too much work and nasty chemicals. I just stick with cutting natural and solid stones, far more straightforward

 

[fredflintstone]

I'm pretty sure that those kinds of treatments pretty much won't work in stable material with low water content like LR Black Opal. No way for the resin to permeate into those cracks and fissures. Some of the blokes that cook Andamooka matrix have mentioned that if they put the really good gem material in to cook with the Matrix that it has little effect on the gem material.

I've partaken in an Opal cook once, was way too much work and nasty chemicals. I just stick with cutting natural and solid stones, far more straightforward

As far as I know, they still have not found a way to stabilize Shewa Opal from Ethiopia. Treatments that they use on Emerald like opticon to stabilize it just does not work on the Shewa material. I've heard rumors that they have found some ways but no concrete proof has been shown to my knowledge.

 

[Garry H (Cut Nut)]

There is a cheap variant of what dentists use. Available on ebay
It's a super glue used with a vacuum.system driven by a garden or washing machine hose with a venturi to suck super glue into spaces then sealed with a UV torch.

 

[Rfisher]

So- strictly entertainment /educationally speaking

Would the opticon-like treatment be considered permanent?
Assuming it’s applied over the whole surface - does it prevent further crazing?
Does the treatment make it more durable to wear and lessen the need for optimum storage environment?

Now setting aside personal feelings of treated gems if you can-
What would a +11ct opal that looks like this one, that isn’t treated, not crazed, nor a doublet/triplet,
ballpark be priced at?

 

[jordyonbass]

Would the opticon-like treatment be considered permanent?
Assuming it’s applied over the whole surface - does it prevent further crazing?
Does the treatment make it more durable to wear and lessen the need for optimum storage environment?

I would think that if a stone is already crazed, it would want to continue that trend as time goes on. Areas where the resin hasn't penetrated will continue to craze over time as the resin is only penetrative cracked areas to hold it together and doesn't actually stop the cause of it (high water content, unstable material). To me, this material is worthless and not worth cutting to sell. Specimen sample only.

The best thing I can do as a cutter with material that seems to want to craze is to work the rough pieces back to colour, then let the rubbed slabs sit for a couple weeks. They will show the crazing issues within that time if there are any. Some Coober Pedy material can be notorious for this and why I don't cut it too often.

 

[Garry H (Cut Nut)]

No one seems to be reading?
Garry H (Cut Nut), post: 5155040, member: 1006"]
There is a cheap variant of what dentists use. Available on ebay. It's a super glue used with a vacuum.system driven by a garden or washing machine hose with a venturi to suck super glue into spaces then sealed with a UV torch.
You can just use the gkue and uv dryer.
You can learn on YouTube how to make the vacuum to suck the super glue into the cracks.

 

[arkieb1]

@Rfisher - depends how long we are talking about and what you do with the opal. As far as I'm aware both the treatment that @Garry H (Cut Nut) mentions which you would assume would be long lasting which is similar to a dentist based glue can still degrade over time, they also use that stuff as far as I'm away to glue/cement some jewellery fixtures into stones and do all sorts of other things with it - (I've seen it used to hold pearls in place and I've seen it used to make sure pendant fixtures drilled into stones stay put, are the two examples that come to mind ) I have seen examples of that failing, because if it is the stuff I am thinking about it too gets brittle over time when exposed to various temperatures and chemicals.

Having said that I don't know how long it would last inside an opal. And yes, Opticon can eventually wear out as well.