Can A Well-Respected Appraiser Detect Ruby Treatment?

[Seaglow]

sja,

At the local level, many burners use borax in the stones as form of standard heating. If the stone has surface reaching features, the lab will detect residue. If not, and the fluxing agents don't get in the stones (say nice clean stones), then there will possibly be no residue. Some burners don't use any fluxing agents. At high temperatures, stone have a possibility to stick together, thus some using the fluxing agent. Personally, I can only accept heat without residue. But even without fluxing agents, corundum can be sent to the burner 2 to 3 times to improve color.

 

[sja1224]

Thanks for all the responses. I called GIA and they said their use of "minor residues" DOES automatically mean that the ruby was heated using a foreign substance (fluxing agent). GIA said there's no way a stone could be "heated only" and "residues" are detected.

I talked with our jeweler again. He was very honest; he acknowledged that this stone was heated with a fluxing agent. He said he'd be able to return the stone to his supplier if we don't want it and he wants us to be happy.

Our jeweler did say he talked with some ruby experts and was told that: almost all rubies are heated with borax, and "minor residues" aren't concerning and it only becomes concerning when it's beyond "minor."

He basically said it'd be a needle in a haystack to find a heated ruby that doesn't have residues that is within our desired specs (round cut, nice red color), and we'd pretty much have to go to unheated rubies if we're not comfortable with a stone heated with residue. Does this sound right?

 

[Seaglow]

It is harder to find unheated rubies than heated rubies without residue given all other specs the same, IMHO.

 

[Arcadian]

Is round mandatory? I'm asking because for rubies (and even sapphires) round comes with a higher premium. A cushion (elongated or square) usually doesn't as it's less wasteful of material. You also open up to additional stones in heat only category.

 

[sja1224]

It is harder to find unheated rubies than heated rubies without residue given all other specs the same, IMHO.

Is this really true? I'm no expert, but I've read that the ruby market is flooded with these "Mong Hsu" rubies that are pretty much all heated with borax.

Plus, lots of places selling "heated" rubies that say they aren't otherwise treated seem to be pretty scammy. For example, James Allen uses their own certificate that says "Treatment: Heated" and I highly doubt all their stones are truly heat only w/o residues. In other words, unless they have a credible lab report showing that there are no residues, I wouldn't believe anyone saying no other treatment.

Is round mandatory? I'm asking because for rubies (and even sapphires) round comes with a higher premium. A cushion (elongated or square) usually doesn't as it's less wasteful of material. You also open up to additional stones in heat only category.

Yes, round is pretty much mandatory; we're trying to do a cluster setting.

 

[Seaglow]

There are more African rubies in the market now than Mong Hsu rubies. Most are glass-filled. Most Mong Hsu rubies have dark purplish modifiers. Most cloudy, bordering opaque. Heat without borax is still used for fairly clean stones and it may take out color zoning or take out purple or brown modifiers, and brighten the color. Many African stones are sold as Burmese at the Myanmar-Thai borders for many years now. I still get to see H only without residue stones with Lotus, AIGS, Gubelin, and GRS Certificates. But ofcourse those treated with borax are way more abundant than those that aren't, and much more are treated with lead glass compared to those heated with borax. But given all else the same, quality unheated is still less than heat only. Many small local labs don't have the equipment in case further testing on minor residues is needed. It is easier to see indications that the stone is unheated such as intact crystals and rutile inclusions, unaltered two-phase inclusions than to determine degrees of heat treatment and detection of very minor residues. Many traders grab rough at source/mine, and know the value of stones is more without residue as form of enhancement. However, many of these goods go to Chinese and Japanese markets.

 

[sja1224]

Following up on this thread.... this is still going on.

Our jeweler told us he spoke with a lot of ruby guys. He said he's been trying to shop for a heated ruby without treatment for us, and the ruby guys all tell him that any heated ruby with NO RESIDUES is *inferior* to a heated ruby that WITH minor residues because NO RESIDUES means that the stone "wasn't heated enough."

Seems odd. Does this make sense, or not?

 

[Arcadian]

Sounds like he's full of BS frankly.

 

[minousbijoux]

Doesn't make sense to me. Sounds like a response of convenience.

 

[marymm]

Following up on this thread.... this is still going on.

Our jeweler told us he spoke with a lot of ruby guys. He said he's been trying to shop for a heated ruby without treatment for us, and the ruby guys all tell him that any heated ruby with NO RESIDUES is *inferior* to a heated ruby that WITH minor residues because NO RESIDUES means that the stone "wasn't heated enough."

Seems odd. Does this make sense, or not?

No, it does not make sense.

Your jeweler is apparently inexperienced in colored gemstones and does not have access to professional reputable dealers of same. Or possibly your jewelry knows better but is giving you this (wrong) story anyway because he is okay with lying to and cheating his customers. Either way, he is not giving you the straight scoop when it comes to rubies/treatment/heat.

I highly recommend you find another dealer, one who is reputable and with expertise in colored gemstones and who backs up his higher-end stones with AGL/GIA certificates.

 

[Burmesedaze]

Mong hsu rubies are much maligned. The ones sent over the border are treated but there are the larger ones or cleaner ones that you can find in the Yangon market untreated. Pretty easy to tell from the black rutile inclusions and when side by side with the Mogok peers, the "blackness" within is pretty obvious. But they are cheaper than Mogok ones and supply is also limited.

It's disturbing to find the market awash with African rubies locally, though most will still tell you upfront here in Yangon, especially if they see you wearing gemstone jewellery

 

[normanintheskywithsapphires]

I'm totally confused about this treatment puzzle and again reinforced in no-heat, basta.

 

[sja1224]

Thanks all for the advice.

What's the best way to maybe find a different jeweler in DTLA who is more knowledgeable about colored stones but is honest? I think our guy is honest, but he deals in diamonds and doesn't know much about colored stones (is that typical?) and is just getting fed bad info by his colored stone sources.

 

[sja1224]

By the way, I called AGL to get some advice. The person who answered the phone wasn't a gemologist but seemed fairly knowledgeable

She told me that almost all rubies are heated using a fluxing agent like borax, and the difference between a heated ruby with residues detected and a heated ruby with no residues detected is that the residues appear when the fissures are at the surface of the ruby.

So, she's basically saying that a heated ruby with no residues detected was still probably heated using a flux, but just no foreign material managed to get in the stone. She said that you can't really heat a ruby without a fluxing agent, kind of like how you cant boil an egg without water.

Is this correct?

 

[partgypsy]

Can't heat a ruby without a fluxing agent. I'm not a gemology expert but I will call bs on that. It is true if you heat the stone high enough, molecules in the environment could in a sense become flux. But you can certainly heat a ruby without adding fluxing agents, just that fissures won't be "healed" without the flux. Heating gemstones of all kinds at low temps has been going on for hundreds upon hundreds of years.

 

[arkieb1]

Great reading;
http://www.ruby-sapphire.com/flux_healing_mong_hsu_ruby.htm

Rubies go - unheated, heat only, then heated with flux or healed to various degrees, then glass filled.

Yes you can find examples of each but you will pay more for the first two than the rest. In many cases rubies that have been healed to a minor degree are commanding high prices these days too. You probably need to decide what you and your budget want and can live with.

 

[Seaglow]

It is possible to heat a ruby with borax and appear in the report as no residue if the stone has no surface reaching fissures. But rubies can be heated without fluxing agent.

 

[sja1224]

It is possible to heat a ruby with borax and appear in the report as no residue if the stone has no surface reaching fissures. But rubies can be heated without fluxing agent.

Good to know. Does it matter as far as quality/appearance/price which one of the two it is? Or is it irrelevant because there's simply no foreign material inside the stone?

 

[arkieb1]

Honestly unless you are looking with a scope you are probably not going to be able to tell. The only rubies that I'd say completely avoid are glass filled ones because if they get near things like heat, any types of acids even things like lemon juice, cleaning products etc it can suddenly reverse the glass filling. And there are different types of glass filling too some are better and better looking under magnification than others.

I'd say if you can afford it go for unheated/untreated or heat only and if not then go for a decent looking well priced stone that has minor residues only.

You can see the difference in pricing/treatments reflected somewhere like this;

https://gemfix.com/gem-category/ruby

https://www.ajsgem.com/burma-ruby-gemstone-ruby-2046340429.html

http://www.thegemtrader.com/June15RubyPage.htm

https://www.topgem.co.uk/index.php/shop/unheated-ruby/untreated-rubies.html

 

[Seaglow]

Good to know. Does it matter as far as quality/appearance/price which one of the two it is? Or is it irrelevant because there's simply no foreign material inside the stone?

The fluxing agent can be used not to fill fissures but also to prevent stones from sticking together when heating or to heal fractures ( not to fill fractures but heat the stones close to melting point that corundum bonds fissures together like melting metal ). If there are no residues, it cannot be differentiated whether a stone is heated with or without fluxing agents. The appearance of healed fissures (not filled) looks the same with or without fluxing agents. Given that fracture healing bonds the gap/fracture/space together, the stone in some cases can be more durable after fissure healing. The difference can be seen though if the is no residue detected and in the presence of inclusions, is in the degree of temperature used as microscopy can detect how altered the inclusions are depending on how high the temperature the stones were subjected to. Gubelin measures in their lab report the degree of thermal enhancement.

 

[Muhammad_Ali]

I would call GIA. Select the option that says, "for technical information...."