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Genuine red coral or fake?

Posted by Jess Forster  
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Jess Forster May 12, 2013 12:31AM
I am thinking of purchasing a piece of red coral and I have found this piece here. I've attached a screenshot I've taken and I was wondering if this piece is genuine or not. I don't know much about coral so I am unsure and I don't wabt to buy a fake. The seller says its from Utah.

Any help would be great :)
open | download - Screenshot_2013-05-12-11-28-52.png (461.7 KB)
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Byron Thomas May 12, 2013 02:10AM
It is a horn coral. Yes it is real
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Owen Lewis (2) May 12, 2013 02:17AM
Not red coral (harvested from a few seas by divers). There is fossilised coral in Utah and some of these fossils are red. Fossilised coral is usually cut and polished across the grain to show the pattern of the coral before it silicified. This is not the graining seen in your picture. But there may be others here who have collected the stuff....



Edited 1 time(s). Last edit at 05/12/2013 02:15PM by Owen Lewis (2).
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Rick Dalrymple May 12, 2013 06:01AM
Jess,

Owen is absolutely right. It is known as Red Horn Coral and it is from Kamas, Utah. I added the location to Mindat so you can post your photo to the site.

Red Horn Coral Occurance, Riley's Canyon, Kamas Area, Summit Co., Utah, USA

Rick
I know I am in my own little world, but everyone knows me here.
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Stephanie Martin May 12, 2013 04:05PM
Hi Jess,

Welcome to mindat!


I agree with the others above. It is genuine horn coral from Utah. It can be red, yellow or grey. It is not rare, meaning that there should be not much trouble in finding more of this available to purchase. This should not be confused with the rare natural red corals from the Mediterranean or Japan. Those corals are the branching type that look more like trees. I wish I had time to do a photo and post to show. Much of this branching type coral is on the market but it is faked meaning real coral that is visually similar that has been dyed, or even synthetic made of plastic. The real stuff is very dear due to the rarity. It was once plentiful in the Mediterranean but it has been largely depleted. They once thought it was a renewable resource in a few years but have since learned it takes hundreds of years to renew. They recently found a pristine pocket in an underwater cave but the location is protected and secret. Since there is no new material of this coming out, only existing supplies are available which drives the prices up. I don't know much about the Japanese material but it would also be rare.

regards,
stephanie :-)



Edited 1 time(s). Last edit at 05/13/2013 03:20AM by Stephanie Martin.
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Jess Forster May 13, 2013 08:26AM
Thanks everyone for you help. :) I have decided to purchase this specimen and I have informed the seller of her mistake that it's Horn Coral and rather than Red Coral.

Rick, thanks for the information on the locality. Once I have received the piece of coral in the picture I'll take a photograph of it and upload it to the page. :)


Many thanks,
Jess
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Jin February 10, 2014 11:19PM
Hi guys,

I am trying to buy some red horn coral, but I have been told that the mine site for red horn coral has been shut down and it's rare to get them now. The seller wants more money on them. Is this true? And on an average how much should I pay for one pound of the raw red horn coral?
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Tony Albini February 11, 2014 01:36AM
Jin,
I have seen horn red coral for sale on eBay. Can't verify if genuine or not but available. As for red coral from the Mediterranian Sea, Mare Nostrum, "our sea" in Latin, one legal concession in Spain has the rights to collect 2.2 KG a year if I remember correctly. Alfredo Petrov has had this material which I bought a piece from him. Most of the red coral sold by the Chinese and others is dyed red, if you break a twig, Alfredo told me it is white inside, buyer beware.

Tony
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Stephanie Martin February 11, 2014 04:26AM
Jin,

A quick check on ebay shows you can buy a pound of Utah horn coral pieces for $50.00. I just looked up "horn coral Utah". Of course you can pay more or less depending on the quality and size as well as who is trying to sell it. Do a little more research before you buy. You can always do an advanced search to check listings that have sold recently, by clicking on the completed items box. This will give you an idea of what they are currently selling for within a reasonable range. Don't forget to include your cost of shipping as depending on where you are located it could be costly for heavier parcels. I saw one parcel that sold for over $500 and one for 300 but that seems to be unusual. Most are selling in the $50 or less range for parcels, but again it depends on how much you are willing to pay for what quality. Sorry I don't know about the location and if it is still producing, perhaps others in the know will chime in.

regards,
stephanie :-)
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Jin February 11, 2014 06:35AM
Thank you guys so much for the information. Yet, the only thing I'm not too sure is that if the mine is really closed or not? Does anyone know where to look up that information? Thanks.
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Mark February 11, 2014 09:54PM
Jin,

Ebay has plenty of them for sale, and the price isn't bad at all!
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Jin February 11, 2014 09:56PM
Mark,

I saw that, but who can confirm with me on the Myth of Red coral Mine has been shut off by government? Because I think if thats the case, then it will be worth to collect them. Thanks.
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Rick Dalrymple February 18, 2014 08:18PM
Mark,

The location is not closed to causal collecting. The road has been closed but you can still hike up. If you have a HCV you can find your way up the back way. There are not active claims anymore. The digging is rough for minimal amounts now. All the loose surface material is gone.

At Tucson I saw pieces the size of a nickle that were polished for $60 each and single horns 3 inches long - polished on the big end for as much as $250 each. There are plenty of people selling rough for $50 to $100 per pound. Eventually, every
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Reiner Mielke February 19, 2014 04:13PM
There should be some dyed horn coral hitting the market soon. LOL
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nandini March 25, 2014 10:44AM
could someone please help me identify these corals if they are genuine natural or not.... thanks
open | download - $_35.JPG (11.2 KB)
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Rock Currier March 28, 2014 12:24AM
There is no way to tell from the photo if they are real or not of if they have been died. You could always send them to an organization like the GIA for verification one way or another, but it would cost you at least $100. There are perhaps test you could run, but it might require that you use some chemicals and or solvents and even then you might not know for sure.

Rock Currier
Crystals not pistols.
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Provo gem man November 13, 2014 10:00PM
It's coral, but only petrified coral from Utah. Actually I just found some in my backyard and work with this frequently. As I am a jeweler. It's not that rare and not "red coral" that is harvested from the ocean.
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Nora Young November 28, 2014 06:10PM
Well, apparently no one in the post above seems to know a lot about testing for real coral. Red coral can be placed in a small bowl of milk (yes, milk) and left for an hour or two. Real coral will turn the milk a pale pink or red without causing any damage at all to the coral itself. It's not colour coming out of the coral, but the red colour reflecting into the milk. Fakes won't do that. And/or if you can find a place on your piece that isn't too visible, place a drop, just a drop or two ,of lemon juice on the coral. If it fizzes up and bubbles, the coral is real. Simple.
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Rock Currier November 30, 2014 01:03PM
I have never heard of the milk test for genuine coral and would personally doubt that it could be relayed upon. In many cases where the cost of testing for "realness" exceeds the cost or approaches the cost of the stones involved, there is no upside to making the test or even developing tests for this purpose. That's why tests to find out if things like agate, or small cut stones are seldom pursued to find out if they are real. Who wants to pay $100 to find out if a $10 stone is real or not.

Rock Currier
Crystals not pistols.
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Alfredo Petrov November 30, 2014 01:25PM
The "milk test" for coral seems like voodoo nonsense to me. And the lemon juice test only tells you that the bubbling coral has carbonate in it; it doesn't tell you whether the red color in it is natural or not.
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Owen Melfyn Lewis November 30, 2014 01:35PM
Nora Young Wrote:
-------------------------------------------------------
> Well, apparently no one in the post above seems to
> know a lot about testing for real coral. Red
> coral can be placed in a small bowl of milk (yes,
> milk) and left for an hour or two. Real coral
> will turn the milk a pale pink or red without
> causing any damage at all to the coral itself.
> It's not colour coming out of the coral, but the
> red colour reflecting into the milk. Fakes won't
> do that.

Sorry Nora but that is a triumph of belief over fact.

Any reddish tinting observed in the milk from a piece of red coral placed in it would be observable immediately. If you have to wait some hours, there has been a colourant transfer from the coral to the milk. This would neither prove nor disprove that the the red corals colour was natural. The crystals of which the skeleton of coral is made up are allochromatic and receive their colour from the organic material carried on the skeleton. Without having tried it, I would expect the amount of colour transfer from corallum rugosa rubrum to milk to be related to some extent to the age of the coral.


>And/or if you can find a place on
> your piece that isn't too visible, place a drop,
> just a drop or two ,of lemon juice on the coral.
> If it fizzes up and bubbles, the coral is real.
> Simple.

Yes. Vinegar works as well and HCl best of all.



Edited 1 time(s). Last edit at 11/30/2014 10:09PM by Owen Melfyn Lewis.
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Alfredo Petrov November 30, 2014 02:18PM
It all depends what you mean by "real" coral. Coral is available by the tons, but of an ugly color. So what gets faked is the color, not the coral... Underneath is still coral, and it will fizz in any kind of acid just like true red coral. So the fizzing test proves nothing (Well, I suppose it proves it isn't plastic, but given the tons of coral laying around on beaches, why use plastic to fake it?). Anyway, a test that does damage to the object if it's "real", and doesn't damage it if it's fake, is not a desirable test :-S

A Corallum rubrum preparation workshop I visited in Spain was using caustic soda (NaOH solution) to remove the organic skin that covers the coral when it's alive. (If one did not remove this skin, one's coral would quickly stink like a dead fish.) Interestingly, orange-red colouring matter is present in both the mineral skeleton (the part we want to polish for jewellery) and in the organic tissues that we dissolve away with the caustic soda. The pigment in the organic part eventually gets precipitated out and sold for several hundred euros per Kg to the natural pigment industry. (So a Corallum rubrum seller who is asked whether any colouring has been added to his or her coral can truthfully say "No, we don't add any color; we take some color out, and sell it!") Even though the natural red color is an organic compound, it seems not to be destroyed by NaOH; it's pretty tough stuff (so it certainly won't dissolve in "milk" either.) Raman spectroscopy is the easiest way to distinguish the real red coral's natural colouring compound from fake dyes.

PXRD is useful (for customs inspectors and the police) for distinguishing the permitted red corals (that aren't on the CITES list of animals prohibited from commerce to save them from extinction), because the permitted species are dominantly composed of calcite, whereas the endangered CITES-listed species have more aragonite.
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Onna Stene November 30, 2014 04:05PM
The best test for coral of any kind is under the microscope. Genuine coral will have growth rings and predominantly even coloring throughout. Dyed coral will have concentrations of dye in rings or cracks. Plastic imitations will have even coloring but no growth rings. There are a few other tests gemologists use to determine ID-if you have a gemologist in your area, they can ID it and probably for less than $100.

Onna
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Owen Melfyn Lewis November 30, 2014 04:52PM
Alfredo Petrov Wrote:
-------------------------------------------------------
> It all depends what you mean by "real" coral.
> Coral is available by the tons, but of an ugly
> color. So what gets faked is the color, not the
> coral... Underneath is still coral, and it will
> fizz in any kind of acid just like true red coral.
> So the fizzing test proves nothing (Well, I
> suppose it proves it isn't plastic, but given the
> tons of coral laying around on beaches, why use
> plastic to fake it?). Anyway, a test that does
> damage to the object if it's "real", and doesn't
> damage it if it's fake, is not a desirable test
> :-S

Alfredo, my only experience of harvesting and preparing corals was during two years in the Caribbean when I was diving 2-3 days a week. That limited my experience to a range of varieties of white coral and and of the black coral that is, of course a conchiolin (near 100% organic) and with no inorganic skeleton.

My experience with red corals is limited to the examination of prepared material currently in the market and ranging in age from (roughly) a couple of years old to 300+ years old. There are perhaps more ways to fake corrallium than for any other gem material. It is also known to be enhanced by dyeing when what has been havested is too light in shade for the best market price. According to O'Donoghue (after Webster) the most certain test for the corallium varieties is longitudinal striations with regularly spaced 'pin-prick' holes that are not found in the reef-building white corals.

> A Corallum rubrum

Touche ;-)

> preparation workshop I visited
> in Spain was using caustic soda (NaOH solution) to
> remove the organic skin that covers the coral when
> it's alive. (If one did not remove this skin,
> one's coral would quickly stink like a dead fish.)

Quite so. In fact the stink starts, full strength as soon as the coral is brought out of the water. I used to use domestic bleach cut to about 30% strength with hot water to clean corals and conch shells. For the latter, a couple of days soaking would not only remove remains of living material but also soften the 'limeing' that builds up on the outside of the shells, disfiguring them, thus allowing the limeing to be brushed off. For some reason this treatment did not affect the colours in or the naturally polished finish on the shells.

> PXRD is useful (for customs inspectors and the
> police) for distinguishing the permitted red
> corals (that aren't on the CITES list of animals
> prohibited from commerce to save them from
> extinction), because the permitted species are
> dominantly composed of calcite, whereas the
> endangered CITES-listed species have more
> aragonite.

Customs desk officers trained in XRD huh? Well, why not? They use fancier techniques to spot bodies, drugs or explosives (even at the trace level) in loaded containers. Trouble with these expensive toys is not that they don't work but that the scale of deployment is simply not commensurate with the volume of items in transit.



Edited 1 time(s). Last edit at 11/30/2014 07:31PM by Owen Melfyn Lewis.
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Tulga December 27, 2014 07:16AM
So how can i find out the red coral is real or not if milk and lemon juice tests are not effective way to identify. I guarantee that the cost cannot tell it is real or fake. In some landlocked countries it is sold in more expensive price than counties surrounded by sea.
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Owen Melfyn Lewis December 27, 2014 11:43AM
According to O'Donoghue (after Webster) the most certain test for the corallium varieties is longitudinal striations with regularly spaced 'pin-prick' holes that are not found in the reef-building white corals.

Nor are they found in plastic.

The best tools are a microscope and good lighting. However, to have any certainty, one should have made some preliminary study of what one should be looking for (the real thing) and the substances commonly used for faking. A sprig of red coral that has been sucked on by babies for a couple of hundred years will not look like a freshly prepared specimen.
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nishchith December 30, 2015 10:19AM

Sir please tell me this is red coral genuine?
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Owen Melfyn Lewis December 30, 2015 12:48PM
It's not possible to say from a photograph and means of testing are limited because the stone is mounted. Examination under a good microscope and with back lighting should reveal some signs of coral growth structure it is is coral. Other likely alternatives are plastic or glass.

That said, I am suspicious of it. Firstly it is cabochon cut and bezel mounted on a white metal ring. Coral is far to soft to withstand wear as a ring stone and one should be able to see signs of wear on the stone (scratches, scrapes etc.. Also, the colour is not right for any red coral had I have seen. The colour (as per photograph) is closer to the flame-pink normally found in the shell and (rarely) pearls from the Queen Conch, Strombus Gigas. https://www.google.co.uk/search?q=strombus+gigas&espv=2&biw=1015&bih=481&tbm=isch&imgil=yP8sy8hcva6QxM%253A%253B82VbUPmZDOhcRM%253Bhttp%25253A%25252F%25252Fwww.stromboidea.de%25252F%25253Fn%2525253DSpecies.LobatusGigas&source=iu&pf=m&fir=yP8sy8hcva6QxM%253A%252C82VbUPmZDOhcRM%252C_&dpr=1.88&usg=__47Jd-oVYXUVtnoIqgF_ditIt7VI%3D&ved=0ahUKEwjjyNamzIPKAhUJVRQKHZ1UAPkQyjcIgQE&ei=fs-DVuORBYmqUZ2pgcgP#imgrc=yP8sy8hcva6QxM%3A&usg=__47Jd-oVYXUVtnoIqgF_ditIt7VI%3D
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Alfredo Petrov December 31, 2015 09:17AM
Color looks more like the pink opal/palygorskite from Peru, which would be hard enough to use in a ring. But I hesitate to ID anything from just a photo with no other information.
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Tõnu Pani December 31, 2015 11:23AM
As far I know - no specific test for coral. Red coral Corallium rubrum consists mainly calcium carbonate /calcite/ and as entity is a colony of coral polypes which makes a specific internal structure. Determination is visual, by recognizing specific structe; possible staining can be detected with acetone, amyl acetate. Gilson product is more homogenous.
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Owen Melfyn Lewis December 31, 2015 01:59PM
Well, its a good ball to kick around on New Year's Eve :-). So I delved a little into my library.

Firstly, I was wrong about the colouration of Corallium Rubrum. It *can* be pink (according to 'Gems' 6th edn). There is actually a much better write-up in the 3rd edn (1975 - the last to be authored and edited by Robert Webster alone and which I also have to hand ).

Palygorskite (with which I am not familiar) is reported (Gems) as a very soft and low density fibrous magnesium aluminium silicate often found in a matted form. Found in several colours, when pink it is sometimes called 'Angel Skin'. However, it sometimes occurs heavily impregnated with hydrothermally formed quartz that hardens, stiffens and makes more dense the resultant natural composite material. I would presume that a pink form of this composite is to what Alfredo refers. Perhaps he would correct or confirm?

To add to the confusion, according to Gems, pink-coloured corallium rubrum is also sometimes referred to as 'Angel Skin' - so go figure :-) It is also implied that this is an anthropomorphic treatment. However, since palygorskite is known to occur in hydrothermal veins, it's hard to accept (for me at least) that the composite must always be man-made.
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Reiner Mielke December 31, 2015 02:30PM
"Red coral Corallium rubrum consists mainly calcium carbonate /calcite/ " actually it is made of calcite and aragonite. Maybe a stain test for aragonite would be a way of distinguish the fake from the real?



Edited 3 time(s). Last edit at 12/31/2015 02:42PM by Reiner Mielke.
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Spencer Ivan Mather December 31, 2015 04:08PM
I have cuit and polished quite a few of these in the 1970's, and if cut across they produce very good gemstones..

Spencer
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Alfredo Petrov December 31, 2015 04:17PM
Nobody fakes coral, as far as I know - why bother? - They take common white coral (so cheap, why would anyone try to make a substitute for it?) and dye it red. So the base (calcite/aragonite) is not the issue. (Well, not counting cheap plastic imitations, which are too banal to discuss.) What needs to be determined is the nature of the coloring - A red organic compound made by Nature, or a red organic compound made by humans? There are several ways of doing that, but certainly not from a photograph!

The gem called "pink opal" or "pink andean opal" from Peru is mineralogically silicified palygorskite, so the hardness is that of silica, and the palygorskite provides the color and opacity.



Edited 1 time(s). Last edit at 12/31/2015 04:38PM by Alfredo Petrov.
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Reiner Mielke December 31, 2015 09:10PM
Hello Alfedo,

Do you know what type of dye is used? If it is organic then bleach should affect it. If inorganic then maybe a chemical test or EDS might do the job. Either way as you suggested RAMAN should work.
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Owen Melfyn Lewis January 01, 2016 12:09AM
Alfredo Petrov Wrote:
-------------------------------------------------------
> Nobody fakes coral, as far as I know - why bother?
> - They take common white coral (so cheap, why
> would anyone try to make a substitute for it?) and
> dye it red.

Not always so, bro. There are a whole heap of simulant methods and materials, some of which date back for hundreds of years. Gilson (now Kyocera) make a nice ceramic copy. Dyed vegetable ivory can also look good. Rubber and gypsum, mixed with powdered marble, isinglas and coloured with red lead. Stained calcined bone. Coral dust that is resin-bonded. Glass or porcelain fakes are found. Plastic is by far the most common found.

The only certain way to sort out corallium rubrum is to know its structure and look for it under magnification with a good light.

Even then there are problems. The weaker coloured real stuff is frequently dyed to improve its appearance/saleability.

> The gem called "pink opal" or "pink andean opal"
> from Peru is mineralogically silicified
> palygorskite, so the hardness is that of silica,
> and the palygorskite provides the color and
> opacity.

Thanks for that.

H&P NY y'all!



Edited 1 time(s). Last edit at 01/01/2016 12:27AM by Owen Melfyn Lewis.
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Reiner Mielke January 01, 2016 02:21PM
I guess that proves not all red coral counterfeiters live near the ocean. :-D
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coral lover February 14, 2016 10:16PM
Hello to everyone! Can anyone help me identify whether these corals are real or fake? There are 76 corals and the total weight is 16 grams. Can you identify how old are the corals? There is a crack in 2nd picture. Thank you!




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Owen Melfyn Lewis February 14, 2016 11:24PM
Not much good news I'm afraid (though you have a pretty necklace).

1. Coral beads are not individual corals but lumps of some larger piece of coral that has been ground down to polish it, sometime in the shape of round beads.

2. There are many different species of coral, not all of which are mineral. Once cleaned, the most usual mineral corals are either white and opaque, or opaque and pinkish-red or dark orangeish-red. The colour is never streaky but solid. If cut thin enough the material will appear translucent or even transparent but several mm thick and viewed by incident light (as in your photos) red coral should look nothing but opaque and with a uniform reddish colour. and the material is never translucent.

3. Your beads are clearly translucent in incident light and are very streaky. Accordingly, and working only from your pics I am confident that the beads are not coral but some other material (My first guess would be glass or maybe plastic (more likely glass).

Since real red coral beads are quite expensive, my opinion may be disturbing news to you. If so, take then to a good jeweller and ask what he would pay you for them. My guess is that, politely, he will refuse to buy.

Sorry not to bring you better news.
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Bob Harman February 15, 2016 12:21AM
YEP, Plastic, glass, or ground up colored coral powder held together with a resin etc. Whatever your necklace beads are, they are not natural coral.......sorry. CHEERS.......BOB
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coral lover February 16, 2016 05:04PM
The seller said the corals are salmon color. I bought it in ebay. I bought it USD 139.
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Ranger Dave February 16, 2016 05:16PM
Take it to a jeweler for verification then contact the seller so you can get your money back.
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coral lover February 16, 2016 05:25PM
I just tested my coral necklace using white vinegar and it immediately formed bubbles within seconds. Now, the portion I tested is not polished anymore :(. Just wonder, how to polish my coral jewelry? Can anyone help?
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coral lover February 16, 2016 06:20PM
If the coral bubbles in vinegar, it means it is genuine? After my vinegar testing, the portion of the coral beads tested turned dull, and I rubbed it with cotton pad with water and very mild soap, it turned out polished again.
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Bob Harman February 16, 2016 06:44PM
Coral is not a mineral per se. Coral is aragonite and that is the mineral. What you might have, as previously mentioned, is powdered aragonite or a similar carbonate. Then it is colored reddish as yours is and the pressed together and held together with a resin. Carbonates react with acids like vinegar. The seller said it was salmon colored.....well anyone can see that it is reddish so that is of no help at all. Yours, also as previously mentioned, is not of uniform color and appears to show areas of translucency. This should not occur if genuine in all respects. In genuine red corals the beads should be more opaque and less variable in color thru out each bead.

As I understand it, the color and pattern of mollusk shells and maybe corals as well is largely the result of their diet. What they feed on.

As was also suggested, take it to an ethical and competent jeweler or similar and have it examined in person. Then educate yourself before spending large sums of money on eBay for lo end stuff. It might be "coral", but it almost certainly has been fabricated. If made from lo end powdered and colored coral, you might not be able to get your money refunded as it is "coral". You asked for help and we are trying to give it to you. CHEERS.......BOB



Edited 1 time(s). Last edit at 02/16/2016 07:26PM by Bob Harman.
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coral lover February 16, 2016 07:47PM
Ok. Thanks Bob. I'll bring it to jeweller to be examined.
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Owen Melfyn Lewis February 16, 2016 11:19PM
CL,
There are many things that your beads may be made of but they are not natural, solid pieces of red coral (expensive and trade in red coral items is now unlawful in most countries - including the US - without a certificate of lawful importation; corallium rubrum is a protected species). You say you paid USD 139 for the necklace? If it was real, pure red coral, you should have being paying several times as much. See https://www.bonhams.com/auctions/23309/lot/272/ for a recent sale of a 2 - 3 mm red coral bead necklace (n.b. the yellow metal is not stated as gold). Or, for larger beads in a single strand, see https://www.bonhams.com/auctions/21943/lot/505/ .

Nor, I'll guess, are your beads dyed pieces of white coral (which are cheap). Beyond that, the possibilities are many. Read this thread from its beginning and you will learn some useful things without the need to write them our again.

@Bob,
A coral is a simple, jelly-like animal (zoophyte). Beginning life as a free-swimming form, it eventually attaches to rocks, old coral skeletons etc., congregating in colonies that secrete a carbonate or conchiolin skeleton on and in which they, the colony, live for the rest of their lives. Corals are the staple food source for some fish species which are adapted to suit that diet.

Where the supporting and shielding skeletons are mainly calcium carbonate, about 5% of the carbonate present will be magnesium carbonate and 1.5 - 4% organic matter. Colouration is organic. The mineral content is microcrystalline - as it is in your own skeleton that is secreted from your organic tissue from before you were born until you stopped growing.

When cut and polished, the only certain method of identification is by microscopic examination to spot the tell-tale growth patterns and pores in the structure - much as one identifies bones, ivories etc.
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AbdulB Sh February 17, 2016 04:56AM
First thing, no one asked the size of beads neither Coral Lover mentioned for coral evaluation, secondly in the photo coral beads are looking to be deeply oiled, and in this oily condition when coral surface is not clear, it is difficult to judge for sure if what could it be....

Its better to carefully wash coral beads then pat dry with cotton cloth and rephotograph again,

Hope it will help!
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coral lover February 17, 2016 09:03PM
Thanks all for your comments. The beads I got are about 2mm.

AbdulB, these are not deeply oiled, its really polished. My camera is not a professional camera, thats why I cannot take even closer look than these photos.

According to the seller, it was a vintage item from 1930. I will try to borrow my friend's professional camera to shot it again and post here. If I bring to jeweller for evaluate, do you know about how much does it approximately costs?
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Owen Melfyn Lewis February 19, 2016 06:31PM
CL,
Just once more.... IMHO, you have a poor fake that has no monetary value.
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Roger Curry February 19, 2016 10:17PM
Here is a video of precious coral. I sold it for more than a few bob. Little Dog
Owen is right.
Regards,
Rog
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Shannon June 09, 2016 12:44AM
Hi, i'm very curious what your opinions are about these pieces? I traded a couple of gold rings and chains at a pawn shop for the necklace and bracelet a least 15 years ago. I assumed they were real red coral because i didn't know there were fakes or dyed or whatever they have now-a-days.
They were vintage when i got them (or at least they weren't new) and now at least 15yrs older since i've had them.
It wasn't until recently i found out that red coral are endangered.
Can anyone tell if they're authentic or dyed or anything about them from the pictures? I included a pic that shows the weight of both together as approx 30grams.

Thank you for any info.

PS. I just saw something that seems to look similar called bamboo coral. I'll have to read more about that but thought i'd mention it too.








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Shannon June 09, 2016 02:05AM
Sorry i misspoke the weight. necklace & bracelet combined are actually 302 grams, necklace is 190 something'
I also think it'll be hard to get a good look because of the picture quality. but i added two more. some with flash some w/o.

thanks for any info. Shannon





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Owen Melfyn Lewis June 09, 2016 10:20AM
Hi Shannon,

I'm pretty sure that what you have is not corallium rubrum, the gem material that has been harvested from the coastal waters the Mediterranean Sea for millennia. There are is also another species of red coral that grows in the waters of the north-western Pacific, of which I have no hands-on experience but your pieces do not look right for that either. Trawl e-Bay, and you will find some stuff that looks like yours - and which is either described as faux red coral or as natural red coral.

You mention bamboo coral. This is a deep cold water coral found between Hawaii and Alaska and this is sometimes crudely cut and dyed an orangy-red and sold as red coral. My guess is that this is what you have. Bamboo coral is roughly tubular lengths of a calcitic coral that are joined by slightly flexible (when fresh) sections of black coral which is not calcitic but conchiolin. Confirmation that a piece is treated bamboo coral requires examination under a microscope. Though there is a write-up in 2006 of bamboo coral in the standard jewellery trade guide to gem materials, there is no mention of it in the 1975 edition of the same work. This might be an indicator as to the period (last quarter of the 20th C) in which treated bamboo coral entered the jewellery market. All pieces of 'native' jewellery of this type seem presently to come from US sources. There is now a ban control on the import/export of all but some Japanese red coral. Ed: These controls are set to to become more severe.

For what its worth,I don't think that your pieces are either plastic or glass.



Edited 1 time(s). Last edit at 06/09/2016 11:17AM by Owen Melfyn Lewis.
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Alfredo Petrov June 09, 2016 10:31AM
Corallium rubrum, the mediterranean red coral, is still being legally harvested, with licences in restricted quantities, in Spain and elsewhere in the Mediterranean, and it is not on the CITES list of endangered species that are prohibited from international commerce, so there shouldn't be any bans on its import/export, at least not within the EU. After the Brexit, who knows.... ;-)
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Owen Melfyn Lewis June 09, 2016 11:39AM
Alfredo Petrov Wrote:
-------------------------------------------------------
> Corallium rubrum, the mediterranean red coral, is
> still being legally harvested, with licences in
> restricted quantities, in Spain and elsewhere in
> the Mediterranean, and it is not on the CITES list
> of endangered species that are prohibited from
> international commerce, so there shouldn't be any
> bans on its import/export, at least not within the
> EU. After the Brexit, who knows.... ;-)

Alfredo,

Just to clear this up (which may be helpful to a few) I have made minor amendment to my post above and add the following:
' Currently, only red coral (Corallium rubrum) is included in an international convention (annex III of the Bern Convention) and in multi-governmental legislation (annex V of the EU Habitats Directive), apart from the extraction limits imposed by certain countries. However, these measures are not enough to conserve these species and control their international trade.' I.e. Corallium rubrum is presently protected under the Berne Convention, EU Habitat Directive and some additional national controls. More comprehensive CITES protection is due to be introduced soon, sponsored by the US.

http://oceana.org/sites/default/files/CITES_English_Coral_Fact_Sheet.pdf

P.S. BREXIT? In a pig's eye! 'Those that the Gods would destroy they first make mad'. :-D
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Alfredo Petrov June 09, 2016 12:21PM
A classic example of wrong priorities by environmental activists: the number of tons of coral harvested commercially is a minuscule amount compared to the several orders of magnitude greater quantity destroyed by bottom trawlers. Oh well, if they're hoping to ban it, get some now while it's still legally available ;-)

Reminds me of the environmental activists' typically knee-jerk opposition to any and all mining projects, regardless of the fact that well over 99% of Earth's surface is not mineralized, so is in no danger from mining; and with land destruction by deforestation, urbanization and bad agricultural practices affecting areas orders of magnitude greater than what is affected by mining... Such is the propensity of humans to get worked up about the sexy topic of the day, rather than by far more widespread and insidious dangers that don't have enough sex appeal to make news headlines.
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Owen Melfyn Lewis June 09, 2016 03:19PM
I do agree in general, Alfredo. That said, there is little doubt that the Mediterranean corallium rubrum has been over-exploited in the last century. It's a very resource and takes centuries of 'no take' rather than decades to regenerate. However, why the US seizes on this as the excuse to ban takes of dozens of species that are not commercially over-exploited can serve only to create more rafts of bureaucracy.
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Shannon June 09, 2016 10:06PM
Thank you very much for this useful information Owen.

I trust your expertise & that it is bamboo coral. Even the black sections you mentioned are present & they're definitely not glass or plastic.
There's tons of similar items online. The only difference is my pieces are not glossy, shiny and new. Mine are old, dull, faded, cracked and the polish is worn.:-D
I didn't really see it until the pictures but, in some of the pieces, especially the necklace, the color seems to be fading because the dye is apparently faded or wearing off.
Too bad i didn't do a little research before doing the trade at that pawn shop. I'm positive they got the better deal on the gold weight alone & i got some pretty painted sticks on a rope! LOL

Thank you again. It was awesome to find this website, you guys are great!
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Owen Melfyn Lewis June 10, 2016 11:34AM
Shannon Wrote:
-------------------------------------------------------
.....
> There's tons of similar items online. The only
> difference is my pieces are not glossy, shiny and
> new. Mine are old, dull, faded, cracked and the
> polish is worn.:-D

Coral is a relatively soft material that abrades fairly easily. Whilst its fine for working into necklaces, earrings and brroches that are well looked after, it is not a good material for bracelets where it will soon show signs of wear or damage. Also, over time and if worn next to the skin (as some necklaces are), coral can absorb sweat and sebum which affect the colour.

> I didn't really see it until the pictures but, in
> some of the pieces, especially the necklace, the
> color seems to be fading because the dye is
> apparently faded or wearing off.

All red coral is dyed - either by nature or by man - and sometimes by both. To understand this one has to think of what coral is and how it grows. The corals are colonies of very small animals that have a communal skeleton that grows as the colony multiplies. Many kinds live in holes in the skeleton but others live on the skeletons surface, For both kinds, the skeleton is produced by secretion from the living tissue of the animals (as human skeletons area). After harvesting the (very smelly) living material is removed and the it is the skeletal material only that is worked into jewellery.

For the hard corals, the skeletal material (mainly some mix of calcium and magnesium minerals) is naturally white. In the red coral species, the red colour is an organic dye produced naturally in the living tissue and some of which stains the hard skeleton as it grows (very slowly). It follows that testing coral for articifial dyeing has to be done with care and without using the most aggressive of solvents. As a rule of thumb, Any coral that is coloured on or near the surface only is likely to be artifically coloured, natural colouring running right through the material. Even then, results are not always conclusive. (this is one area where experience with the coral type is of real importance). As with conch shells and conch pearls, the pinkish reds are quite prone to fading with prolonged exposure to UV. I have pieces self-collected almost 50 years ago that though always kept indoors have lost most of their brilliant colour. This bleaching over time is also a surface effect, the bleaching progressing deeper over the years :-S

> Too bad i didn't do a little research before doing
> the trade at that pawn shop. I'm positive they got
> the better deal on the gold weight alone & i got
> some pretty painted sticks on a rope! LOL

I guess so. Write it off to experience (always the best the school - but the fees are high). The other saying I like is 'Show me a guy who has never made a mistake and I will show you a guy who has never done anything' ;-)
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Cameron Worcester August 13, 2017 02:47AM
I bought this piece of red coral. Can anyone tell me more about it. The shop owner said it was a second rung piece from china.
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