Questions regarding resin & opals

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Shea_O
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Questions regarding resin & opals

Post by Shea_O »

Hi all,

I’m working on three different opal projects and two of them potentially need resin coatings.

So I understand that it’s necessary to disclose any kind of chemical processes you put your opals through, like if the opal was placed into a hot oil bath, but what about with resin coatings? The catch with the hot oil bath is hat it alters the visual appearance of the opal from its natural state, and I can see why this deastically affects value, but what about a chemical application (resin) that doesn’t affect the optical properties? Does resin coating your opal always have to result in a “degraded value”?

One of my projects, the matrix opal, is composed of a opal breccia mix that can pilish up well - surprisingly - but looks much better aesthetically with a resin coating on it and buffed up to a glossy surface. Much more glossy and glass-like than the natural breccia surface.

I would prefer to use resin on my future projects with this matrix opal but I need help with choosing a resin that won’t alter visuals due to a chemical reaction or can be removed without harsh chemicals.

And I also wonder abt putting a resin coating on some of my VV opal, I wonder if I should? What to use?

Thanks
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PinkDiamond
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Re: Questions regarding resin & opals

Post by PinkDiamond »

John would be the one to answer your question on the VV opal, but any sort of treatment to a natural stone is a treatment that must be disclosed, so when you sell treated opals you'll want to explain that it was done to stabilize the opal to keep it from crazing if you want to use it as a selling point. Also, unless a product has been around for a good number of years, there's no way to tell if it will eventually have a change in appearance, such as yellowing. Hope that helps.
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rocks2dust
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Re: Questions regarding resin & opals

Post by rocks2dust »

Yes, it needs to be disclosed. All resins fillers and stabilizers eventually will alter chemically over time. Despite breathless claims implying otherwise, even the "non-yellowing" resins will yellow to some degree as their UV inhibitors break down over time, and thus will eventually affect the appearance (and perhaps other properties). Treatments do not necessarily affect value - some materials such as ammolite wouldn't be possible to use without them. However, when comparing a treated piece with a stable, but untreated, similar piece, the untreated piece is going to have a higher value. It is thus necessary to disclose the treatment.

Added: I see Pink has answered in a similar vein. I wanted to underline her point about not knowing how some treatments will fare over time. There have been some materials that have been marketed as permanent and stable that have proved nothing of the sort under real-world conditions. Some have released acidic by-products (causing damage to settings and adjacent jewels), some have become brittle, some have turned opaque, etc. The worst problems, IMO, come with those treatments that are non-reversible, or very difficult to reverse, which closes off the option to remove the treatment (and possibly re-treat) once degradation is noticed.
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Shea_O
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Re: Questions regarding resin & opals

Post by Shea_O »

Thank you both, Pink & R2d, your information is great!

I have a mentor of sorts who answers my questions far too infrequently and I have lots of questions. I get replies from this individual so infrequently that I still feel as though I’m undertaking this opal journey on my own. I’ve taught myself a great deal so far, and that information wasn’t all free either. So I really do appreciate tips and information from you all - it’s hard to get and as far as opal is concerned, mistakes are expensive if not fatal to your goals. I’ve learned to not have specific plans for my opal, in the sense that they will do what they want to do. But I don’t have enough inexpensive rough to dink around and experiment with right now. So I ponder for weeks on the more specific questions until my mentor responds.

So, another question: I was cutting some rough and broke a stone into 3 equal size pieces and my mentor brought over a bottle of cyanoacrylate “super-T glue (thin)” and we glued my opal back togeher and about a half hour later I was back on the wheel, grinding on it some more.

I wonder if the cyano could work as a makeshift “resin” of sorts, just for the sake of enveloping the stone with a clear and semi-soft coating? I worry about the the removal of the glue at a later date though... about the alcohol/acetone needed to remove it. I don’t know if acetone will have adverse affects besides the obvious implications of dessicatting the stone too rapidly/unevenly... especially worrysome with VV opal..

I have seen how the cyano looks on both my Ethiopian black opal and on my Indonesian matrix opal and it gives it a glossy-glass like look that I imagine would look great as a “polished surface” but don’t know if I’ve got my head in the wrong place for what I want to do.

I have seen youtube videos hat Mining America has posted mentioning that he uses a water base resin, when he has to - but that certainly wouldn’t be acceptable for jewelry if your resin washes off in the rain.... Anyways, I wonder what resin(s) you may reccommend that you personally like, if any, and if you know if resin coatings are able to be polished/buffed to a glassy surface.

Edit: I use a Diamond Pacific Genie w/ diamond grit wheels when with my mentor and when by myself I use hand dremels with diamond grit pastes. Please share with me if you know anything about whether my dremel pastes will make resin/glue coatings become cloudy... I suspect that might happen and have heard of people clouding up hydrophane ethiopian stones accidentally by using pastes.


Thanks
mick
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Re: Questions regarding resin & opals

Post by mick »

You wont find much info on resin and indo and ethiopian opal
steer clear of resin its not needed unlless you want to set an opal in resin.
learn to polish no one will buy an opal covered in resin you will waste your money
unless its opal set in resin, like keyrings etc
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SwordfishMining
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Re: Questions regarding resin & opals

Post by SwordfishMining »

Any process other than time and humidity should be disclosed. All resin DOES alter the optical properties to varying extents and no opals are exactly the same. Never will a treated stone be worth close to what a natural one is. 10% is the figure natural cutters try to use but its closer to half for the real looking ones in commercial grades. The only way they could sell the washed out matrix from Andamooka was treating it with black so the POC was visible. So in that case treatment made it salable, the best was always salable but too rare to set a standard. Precious opal sets the standard they have to come up to, or undercut to sell more specifically. Cyano can flow coat a "polish" like the Ammonites use Excel, but buyers wont rate it as highly unless the entire line is all done that way, like it is except for the few naturals I have seen, it is all protected being a coating on mudstone. I have found not treatment or resin oil whatever (I'm not breaking my back worrying about it) that actually will penetrate the opal structure for a satisfactory seal. Others do but im not privvy to their hours of experimentation. Skills hard earned are not given away. They dont talk as it is a livelyhood, not just a method that competitors would not use against you to steal all your buyers. They will do my stones for me but not tell me how to not use them? The last resin i used was Opal Cure on my pendent. They are much better for saving crazed stones to be set cheap instead of saving any great stones from crazing. The Auzzies only mention resin when they are repairing their broken stones as for the most part they just replace the bad ones as a cost of business. Most people dont go back for the warranty. I knew of chemists at Standard Oil and 3M who died without figuring out the secret in their corporate chemical labs. When it is figured out, dont think the inventors are sharing either. They will have to take on the australian opal lobby and disprove the big lie that "Virgin Valley Opal " is impossible to cut and use in jewellery. People buy the plastic opal in costume jewelry all the time so there is room in the market for price point blacks, treated or not. Im barely familiar with pastes. I cut on a Genie. Naturals or Startbonded matrix. I like the cyno because it is obvious and it does not soak into the opal and treatment can be seen with a loupe. Until they fix that, I cut naturals as that is what people want to buy and wirewrap the treated ones because a lot of people just want to wear a pretty, not resell it at a profit down the road. I would try Paleobond next if i was going to. They say it's yellowing is less decades down the road. Once treated then cut, then put in solvent, frees the glued in pieces and it wont hold more times than not. Acetone is a fast dryer that has to be accounted for. Soak it out in water many times before drying to have water evaportating not acetone. That killed an half hour
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mick
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Re: Questions regarding resin & opals

Post by mick »

SwordfishMining wrote:Any process other than time and humidity should be disclosed. All resin DOES alter the optical properties to varying extents and no opals are exactly the same. Never will a treated stone be worth close to what a natural one is. 10% is the figure natural cutters try to use but its closer to half for the real looking ones in commercial grades. The only way they could sell the washed out matrix from Andamooka was treating it with black so the POC was visible. So in that case treatment made it salable, the best was always salable but too rare to set a standard. Precious opal sets the standard they have to come up to, or undercut to sell more specifically. Cyano can flow coat a "polish" like the Ammonites use Excel, but buyers wont rate it as highly unless the entire line is all done that way, like it is except for the few naturals I have seen, it is all protected being a coating on mudstone. I have found not treatment or resin oil whatever (I'm not breaking my back worrying about it) that actually will penetrate the opal structure for a satisfactory seal. Others do but im not privvy to their hours of experimentation. Skills hard earned are not given away. They dont talk as it is a livelyhood, not just a method that competitors would not use against you to steal all your buyers. They will do my stones for me but not tell me how to not use them? The last resin i used was Opal Cure on my pendent. They are much better for saving crazed stones to be set cheap instead of saving any great stones from crazing. The Auzzies only mention resin when they are repairing their broken stones as for the most part they just replace the bad ones as a cost of business. Most people dont go back for the warranty. I knew of chemists at Standard Oil and 3M who died without figuring out the secret in their corporate chemical labs. When it is figured out, dont think the inventors are sharing either. They will have to take on the australian opal lobby and disprove the big lie that "Virgin Valley Opal " is impossible to cut and use in jewellery. People buy the plastic opal in costume jewelry all the time so there is room in the market for price point blacks, treated or not. Im barely familiar with pastes. I cut on a Genie. Naturals or Startbonded matrix. I like the cyno because it is obvious and it does not soak into the opal and treatment can be seen with a loupe. Until they fix that, I cut naturals as that is what people want to buy and wirewrap the treated ones because a lot of people just want to wear a pretty, not resell it at a profit down the road. I would try Paleobond next if i was going to. They say it's yellowing is less decades down the road. Once treated then cut, then put in solvent, frees the glued in pieces and it wont hold more times than not. Acetone is a fast dryer that has to be accounted for. Soak it out in water many times before drying to have water evaportating not acetone. That killed an half hour


Use three fingers, only take 15 min then
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SwordfishMining
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Re: Questions regarding resin & opals

Post by SwordfishMining »

I should file cut out of the replies to paste every time it comes up. I dont wonder why my hands are stove up like they are. (HAHAHA Good One as if you didnt know it!)
I'll jump over my shadow. https://www.virginvalleyopal.com"
Opals & more at my ESTY store https://swordfishmining.etsy.com"
mick
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Re: Questions regarding resin & opals

Post by mick »

I tried one of those speech to text things once, took longer than typing as you have to go back and correct it plus sitting talking outloud to yaself not good. As I type, theres a kangaroo asleep in the winter sun down the road, it aint moving. I seen their scat about 50metres away so I knew they were close but never seen one asleep like that so close to houses in daytime i.e. 10 yards from back fence but it is a lovely day. 60f and no wind or clouds.
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SwordfishMining
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Re: Questions regarding resin & opals

Post by SwordfishMining »

Nice. I like to see wildlife as long as its not making a mess of my bower, like the mud dauber wasp that said high in the bathroom this morning. Ant food. AND i need to do something about the harvester ants that are thriving a bit too well too close to my house not that there are at least 4 other species about if they were gone or the termites in any wood that touches the ground. But I digress. Today is our town BBQ roping and dance. Last few weeks were thunderstormy but it looks like summer is here temps 70-80F days and 50s nights with a breeze both ways daily. My ex was just here and really wanted to see the wild burros while we were running around sightseeing/mining/visiting with her new guy. The refuge fenced the burros and horses all out and we never saw any. When we got back to the hotel the owners have a pair of miniature donkeys that came poked their head around a building begging. They also have goats (two white unicorns, 1 polled right and 1 polled left) keep the ashtrays clean. Oh well ive already missed the kids sheep wrangling and barrle riding even if i only go out there to eat at the concessions. Maybe i'll be lucky and win one of the guns raffled off this year. I donate things into gift baskets that are silent auctioned bid for. Great fun.
I'll jump over my shadow. https://www.virginvalleyopal.com"
Opals & more at my ESTY store https://swordfishmining.etsy.com"
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