Minor oil vs no oil Muzo Green emeralds

[budmanbudman10]

Hi there,

Does anyone have advice on minor oil emeralds vs no oil emeralds?

Especially interested in knowing if, in PSers opinion, minor oil emeralds are riskier to set or need to be re-oiled every few decades to look good (vs. no oil emeralds)?

For sub-carat emeralds (Muzo Green, GRS cert), what do you think of $2,950/ct for minor oil and $4,600/ct for no oil?

Thank you

 

[partgypsy]

It's simply going to be hard to find non-oiled emeralds. I would say if you can afford it and you want more peace of mind sure get a non enhanced (non oiled) emerald. For the rest of us mortals even a minor oil treatment fine muzo emerald is a rare creature and still a treasure. Setting any emerald is more riskier than say many other types of stones. Risks would involve the type and number of inclusions especially surface reaching inclusions near the prongs.

The oiling is for appearance, it does not make the stone more or less durable though it does hide the appearance of inclusions. For all emeralds you should not sonicate the stone, and of course let the setter know it is an emerald before having work done.

 

[LilAlex]

Maybe not helpful but you can get a terrible no-oil emerald. You (and I) infer that no-oil = quality so high that oiling would not improve the appearance. But like unheated sapphires, there is a lot of bad material out there and some vendors know to push the no-heat or no-oil seal of approval.

My threshold would be insignificant to minor for AGL. I don't like the "present" vs "absent" nomenclature that some labs use.

I would much prefer a spectacular minor-oil to a so-so no-oil gem. (Same goes for heated sapphire.)

I would not buy a "moderately enhanced" and I'm not entirely sure why.

 

[Kaycee2018]

I’m new to emeralds, but after a ton of research I agree that the appearance (color, clarity, etc.) are key in deciding. All things being equal though, I’d go with as minimal treatment as budget would allow. Even if that meant going smaller in size. But I also think priorities are different for everyone. GLD

 

[budmanbudman10]

Thanks @partgypsy, @LilAlex, and @Kaycee2018!

Really appreciate the input and advice!

Will definitely look for more than just level of treatment - I promise

With regards to my earlier question, I was wondering if emeralds treated with cedar oil imply more surface-reaching fissures that may mean riskier setting. But I may be overthinking this haha

 

[voce]

Maybe not helpful but you can get a terrible no-oil emerald. You (and I) infer that no-oil = quality so high that oiling would not improve the appearance. But like unheated sapphires, there is a lot of bad material out there and some vendors know to push the no-heat or no-oil seal of approval.

My threshold would be insignificant to minor for AGL. I don't like the "present" vs "absent" nomenclature that some labs use.

I would much prefer a spectacular minor-oil to a so-so no-oil gem. (Same goes for heated sapphire.)

I would not buy a "moderately enhanced" and I'm not entirely sure why.

In my instance I would worry that if I bought a moderately enhanced emerald and successfully set it, after a number of years if the enhancement (if it's oil) has dried up, the emerald might not look the same and might look uglier over time.

With minor, I assume that since not much oil has penetrated, what I see is what I get, and the emerald's appearance is unlikely to change over time.

 

[chrono]

I’m not opposed to the newer resin for this reason: it is permanent and doesn’t dry up (and need re-treatment, unlike oiling). Regardless of oil or resin, my preference is minor treatment if budget is tight.

 

[voce]

Hi there,

Does anyone have advice on minor oil emeralds vs no oil emeralds?

Especially interested in knowing if, in PSers opinion, minor oil emeralds are riskier to set or need to be re-oiled every few decades to look good (vs. no oil emeralds)?

For sub-carat emeralds (Muzo Green, GRS cert), what do you think of $2,950/ct for minor oil and $4,600/ct for no oil?

Thank you

I agree with @chrono regarding preferring the more modern resin treatment, which I think is more stable.

Back to OP's original question, Muzo color quality ranges so much that, unless it's top top top duck neck vivid blue-green emerald color with sheen we're talking about here, I would not pay the premium simply for the origin and that minor/no treatment, considering the sub-carat size.

 

[Bron357]

In my humble opinion you should buy emeralds based on colour and clarity, what “speaks” to you, provided that the origin is certified as is the treatment.
minor oil is normal, it’s rare to find “non oiled” and to me personally the vast increase in price per carat doesn’t justify it.
Its a niche market for superb, unoiled Munzo emeralds and you need deep pockets to buy them. For me, better a bit bigger in size for the $$$$ as long as minor oil.
any emerald requires an experienced bench, they are brittle, can’t handle a torch and mustn’t be “pickled” or put in an ultrasonic cleaner. I had my emerald and diamond ring re rhodium plated and resized, the emerald was unset and reset to do this so more expensive.

 

[SallyBrown]

Hope I’m not thread jacking. But does anyone know about emerald eternity bands? Are the stones likely to change in appearance over time? Isn’t it hard to find out what all the little French cut/other cut stones were treated with?

 

[chrono]

It is easier to find clean melee sized stones but I always presume they’re treated in some form or fashion. For emeralds, oil is highly unlikely but coloured resin is a good possibility. I always presume heat or BE treatment for ruby eternity.

Eternity can be sent to a lab to verify (can check in setting) but most people don’t due to the cost (checking costs more than the ring itself).

 

[budmanbudman10]

Really appreciate the advice @voce, @chrono, and @Bron357!

Thank you

I may come back with some potential options and their pricing soon if that's ok

 

[Bron357]

Hope I’m not thread jacking. But does anyone know about emerald eternity bands? Are the stones likely to change in appearance over time? Isn’t it hard to find out what all the little French cut/other cut stones were treated with?

I would adore an emerald eternity band myself but the reality of wearing one is fraught with problems unless Chanel set (lowered in setting) for protection.
Emeralds are relatively “soft” gemstones and brittle. This means it’s easy to abraid or chip them ie damage the table (top surface).with frequent wear and when worn alongside / underneath other rings.
As for treatments, it wouldn’t be practical to test each stone so you would buy assuming them oiled.

 

[Skyjems]

Hi there,

Does anyone have advice on minor oil emeralds vs no oil emeralds?

Especially interested in knowing if, in PSers opinion, minor oil emeralds are riskier to set or need to be re-oiled every few decades to look good (vs. no oil emeralds)?

For sub-carat emeralds (Muzo Green, GRS cert), what do you think of $2,950/ct for minor oil and $4,600/ct for no oil?

Thank you

My advice from experience is that the clarity change in a minor oil stone is USUALLY fairly negligible (but there are always exceptions that prove the rule) most stones will want to be repolished every twenty five years or so anyway, at which point you can get it reoiled.

So, if the price weren't a factor... Which is prettier? I'd love to see any photos.

 

[PrecisionGem]

Emeralds are NOT relatively soft stones, they have a hardness of 7.5 to 8 which puts them at or a little harder than garnets and tourmaline. However many are very included, so what happens is you bang them, and they can break off small pieces.

As far as labs testing for oil, even stones that have not been officially oiled will at times show traces of oil and get oil indicated on the report. This can be from the cutting oil on the lap when polishing, as small amounts can get forced into surface crevices. Also, pretty much every one who deals with rough emeralds, or that matter many other stones tends to squirt baby oil on the stones as this makes them show better. A properly oiled emerald is oiled after cutting, but these small amount of oil in the rough can also show up to a lab.

There is a guy from Brazil I would buy emerald rough from in Tucson, and he always carried a bottle of baby oil with him. He used it so much it was always on his pants, if you first met him you would have thought he pissed his pants as they are so stained in the front.

 

[chrono]

I'm sorry @PrecisionGem but I imagine having butter fingers when picking up emeralds and they go flying every which way with my greasy oiled hands.

 

[Sydneyphoenix]

Hello, a lurker here for many years but took the plunge for sign-up now I am at the cusp of starting my jewellery collection (currently just a few Akoya pearl/gold rosaries and a single deep green-but not quite imperial-jadeite cabochon). Looking to start with Imperial jade (just one for heirloom will do...), Burmese ruby and Colombian Emerald, as well as native Australian Argyle diamonds, for enjoyment and investments as able over time. I thought I will ask a question related to this topic rather than start a whole new thread...hope it’s okay.

Just in regard to top-notch emerald, I understand “Muzo” is the ideal signature of Colombian emeralds in terms of colour and “no oil” is the best in terms of treatment spectrum, though vast majority undergo some treatment. And it looks like you are looking at tens of thousands of dollars per carat for certified no-oil Muzo emerald. Now if you have to sacrifice one character over other (but only next rung down in quality rather than horrible colour or excess treatment) which would you rate as more important?

To illustrate this inquiry, perhaps I might use two emeralds in current Leibish & co stock, both going for roughly U$17,000. The first stone (1.88 ct) has certified Muzo green colour per GRS (I know some here do not like GRS’s descriptives for colour but I guess that’s for another day) but have insignificant oil treatment detected. The other stone assessed by AGL (1.00 ct) apparently has no indications of oil treatment but AGL doesn’t make determination as to colour quality in terms of layperson descriptives (unless I am not reading the AGL certificates right); it nevertheless is certified as of Colombian origin (and perhaps May be classified as Muzo green if GRS was doing the assessment??) and a very pleasant green with a hint of blue, aside from whitish surface defects on one corner that can be easily hidden with a prong. Given the first stone with Muzo colour is almost twice as large (but still under 2ct), I imagine “no-oil” character fetch more of a premium over Muzo colour.

Am I reading this correctly, that as long as the other parameter is met (intense to vivid green colour Colombian without Muzo moniker vs insignificant or minor oil treatment Muzo), jump from minor oil to no oil treatment is rarer and worth more than “normal” vivid green to Muzo green, assuming other sizes and clarity are similar? For the same money which one would you buy if given a chance...thank you in advance for any feedback and be nice to a newbie!

1.88 carat, Green, COLOMBIAN Emerald, Emerald Shape, Insignificant, GRS, SKU 469102

1.88 carat, Vivid Green, Emerald shape Gemstone, graded by GRS. An excellent Green Gemstone that has a wonderful sparkle. For more information about this item please contact our customer service department.

www.leibish.com

1.00 carat, Green, COLOMBIAN Emerald, Emerald Shape, No Oil, AGL, SKU 304334

1.00 carat, Green, Emerald shape Emerald, graded by AGL. A beautiful Green Gemstone that's full of life. For more information about this item please contact our customer service department.

www.leibish.com

 

[voce]

@Sydneyphoenix you shouldn't form conclusions based on how one vendor prices vivid green from Muzo vs no oil. How much vendors each value color, cut and clarity is relative.

Also, AGL DOES grade color, in their grading report. It's more expensive, and very few stones get the top grades, so it's not a popular report with vendors. When vendors do AGL, 99% of the time they go with the Prestige report that just says origin, not the full AGL Grading Report that rate color and cut on a 1-10 scale.

 

[whitewave]

Hi there,

Does anyone have advice on minor oil emeralds vs no oil emeralds?

Especially interested in knowing if, in PSers opinion, minor oil emeralds are riskier to set or need to be re-oiled every few decades to look good (vs. no oil emeralds)?

For sub-carat emeralds (Muzo Green, GRS cert), what do you think of $2,950/ct for minor oil and $4,600/ct for no oil?

Thank you

Even Ed at Wildfish gems is now selling oiled emeralds because at this point, it’s near impossible to find a truly unoiled emerald.

 

[voce]

Even Ed at Wildfish gems is now selling oiled emeralds because at this point, it’s near impossible to find a truly unoiled emerald.

I think the rarity of oiled vs unoiled MOSTLY depends on the origin.

I admit Muzo unoiled is very rare. However, let's not kid ourselves that Muzo is the only emerald origin. It is still quite possible to get unoiled emerald from Afghanistan, Russia, Zambia. So if we're talking about the rarity of unoiled, the origin and color MUST be discussed, too.

I don't think Ed from Wildish Gems sells emeralds from all origins, so again we should be careful not to extrapolate what seems to be true for one vendor (representing only a small percentage of market share) to the entire market.

For example, the small square emeralds are 0.14-0.18 ct each, from Brazil, minor oil, a vivid duck neck green, and were priced at $3600/ct in February of 2020 because they are the best color quality available.


And in November 2020 I said yes to this Russian emerald, 0.78 ct, unoiled, medium and neon blue-green, for $3000/ct.


Given the rarity of both, I do not believe I overpaid for either. But unoiled is not impossible to find with certain origins, and not necessarily priced above the finer color minor oiled.

 

[whitewave]

Here is Ed’s take on the issue....

I only post it because he had something to say about it and he put his thoughts in writing on his webpage.

The #1 Web-Shop for Fine Natural Gems and Jewelry in Europe since 2003 - Emerald

fine untreated emeralds, emerald gemstones for sale, fine oil-only emeralds

www.wildfishgems.com

 

[voce]

This at the bottom of the page is what Ed had to say.

I don't think this means the same thing as impossible. And--make note that this simply says this is about oiled vs unoiled emeralds, not MINOR oil vs unoiled.

Of all the emeralds sold, maybe 2% or less will be certified by GIA as F1 or by AGL as minor oil, and maybe 0.5% or less will be certified by either as unoiled/untreated.

Just want to say, a lot of Ed's certificates on the emeralds are from labs with lesser reputation compared to GIA and AGL and don't try to quantify the degree of treatment aka oiling. So it may very well be the case the emerald itself is untreated, and it's just that the lab that Ed is sending the emeralds to just doesn't check for the extent of treatments, so will just put oil on all lab reports.

Again, one vendor does not represent the whole market.

There are some vendors who insist that untreated/unheated sapphires don't exist. So I just take what any one individual vendor could say with a grain of salt.

 

[T L]

There’s also faint oil. That might be an option.

 

[Sydneyphoenix]

Thank you for all the responses thus far.
So I can assume that above certain level of general quality, “unoiled” character is more valuable than “Muzo green” moniker as far as fine Colombian emeralds are concerned, due to relative rarity? I understand it means nothing if the unoiled emerald have horrible colour and inclusions.

 

[Sydneyphoenix]

There’s also faint oil. That might be an option.

Yes, GRS has “insignificant” between “no oil” and “minor”...

@Sydneyphoenix you shouldn't form conclusions based on how one vendor prices vivid green from Muzo vs no oil. How much vendors each value color, cut and clarity is relative.

Also, AGL DOES grade color, in their grading report. It's more expensive, and very few stones get the top grades, so it's not a popular report with vendors. When vendors do AGL, 99% of the time they go with the Prestige report that just says origin, not the full AGL Grading Report that rate color and cut on a 1-10 scale.

Should look into it for my purchases worth more than $5K or so, thank you. Do you know if they do this for imperial jade too?

I think the rarity of oiled vs unoiled MOSTLY depends on the origin.

I admit Muzo unoiled is very rare. However, let's not kid ourselves that Muzo is the only emerald origin. It is still quite possible to get unoiled emerald from Afghanistan, Russia, Zambia. So if we're talking about the rarity of unoiled, the origin and color MUST be discussed, too.

I don't think Ed from Wildish Gems sells emeralds from all origins, so again we should be careful not to extrapolate what seems to be true for one vendor (representing only a small percentage of market share) to the entire market.

For example, the small square emeralds are 0.14-0.18 ct each, from Brazil, minor oil, a vivid duck neck green, and were priced at $3600/ct in February of 2020 because they are the best color quality available.

Some lovely melee emeralds there!!

 

[voce]

Thank you for all the responses thus far.
So I can assume that above certain level of general quality, “unoiled” character is more valuable than “Muzo green” moniker as far as fine Colombian emeralds are concerned, due to relative rarity? I understand it means nothing if the unoiled emerald have horrible colour and inclusions.

All that I've written was going against drawing a simple conclusion like this. My answer would be: it depends on the vendor. Leibish and Wild Fish Gems are pricing unoiled emeralds higher, but you could find it to be otherwise with different vendors.

 

[voce]

Should look into it for my purchases worth more than $5K or so, thank you. Do you know if they do this for imperial jade too?

AGL doesn't grade jade. I don't think that they even do jade. You should ask the jade experts (@icy_jade @Burmesedaze @mellowyellowgirl @Bluegemz) what lab they would trust to purchase heirloom quality imperial jade.

 

[Sydneyphoenix]

AGL doesn't grade jade. I don't think that they even do jade. You should ask the jade experts (@icy_jade @Burmesedaze @mellowyellowgirl @Bluegemz) what lab they would trust to purchase heirloom quality imperial jade.

Shame, I thought I found my jade grader. The market is really niche in Australia, most of valuers seem to be very nervous about it. I know labs in HK and Singapore are highly regarded and AIGS seems to be doing quite a detailed analysis for colour and cut...

 

[icy_jade]

AGL doesn't grade jade. I don't think that they even do jade. You should ask the jade experts (@icy_jade @Burmesedaze @mellowyellowgirl @Bluegemz) what lab they would trust to purchase heirloom quality imperial jade.

I like Hong Kong Jade & Stone Laboratory in HK - also used by auction houses.

GIA is ok, Nanyang lab (in Singapore), Tulab (Taiwan), GIT (Thailand) are the ones I trust.

 

[Sydneyphoenix]

I like Hong Kong Jade & Stone Laboratory in HK - also used by auction houses.

GIA is ok, Nanyang lab (in Singapore), Tulab (Taiwan), GIT (Thailand) are the ones I trust.

Without going completely off-topic, how does AIGS jade report fare compared to HK, Singapore and GIT, they do seem to assess cut, polish and clarity as well as colour which is encouraging.