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Fakes & FraudsAre these real or fake red coral

22nd Jul 2017 19:25 UTCAshley Wise

Over the years I've acquired a few "red coral" specimens. Some were from before I knew there were fakes.

I'm curious on your best guesses on what these actually are?

- True red coral from Mediterranean/japan. My understanding is this is hundreds of years old but not fossilized.

- Other red coral that is real coral and not dyed, such as from utah, possibly fossilized?

- Regular coral that's been dyed

- Some kind of plastic or glass or resin fake

I have one picture with the four specimens. I took additional photos using microscope mode on my camera.

Four of the large piece. This one looks almost like the red is a laquer layer, the bottom is solid red coating like the sides which doesn't make sense. The break at the top however shows tree rings going through the red, though that could be just dye bleed. The fact that the break shows white on the inside seems to make me think it's dyded. But the coral itself seems very crystalline, almost like it might be real fossilized coral.

Three of the small pale-pink branching piece. This one seems most likely to be regular coral that's been dyed.

Four of the small deep red glassy-looking pieces. These are the ones I was most curious if they might be the "real" thing. They seem almost gem quality. They almost look and feel like plastic resin, but the microscope photos look like stone, and there's clear texture in them.

22nd Jul 2017 19:26 UTCAshley Wise

These are the large one photos

22nd Jul 2017 19:27 UTCAshley Wise

The last one of the large specimen

the first two of the pale specimen

22nd Jul 2017 19:29 UTCAshley Wise

the last one of the pale specimen

the first one of the glassy specimen

22nd Jul 2017 19:29 UTCAshley Wise

And the last three of the glassy specimen

thanks y'all!

22nd Jul 2017 20:40 UTCGary Weinstein

Ashley,

The large one looks like dyed real coral. Sometimes made into beads, etc. and called apple coral. Prob from Taiwan or Philippines.

The glassy red and orange are polished branches of Mediterranean gem corals. The pink is real but comes from somewhere else.

Best,

Gary

22nd Jul 2017 20:50 UTCDave Owen

Left two look like nice Mediterranean pieces the big one dyed Chinese not sure on the other.

22nd Jul 2017 21:08 UTCOwen Lewis

Ashley,

I think you're right to approach with caution. The large piece in particular does not look at all right to be any coral I have seen (but I haven't - has anyone - seen 'em all).

Start from basic facts and then do some testing?

At a glance, you do *not* have any of the conchiolin based corals but from the pics only, a calcereous coral or corals cannot be ruled out. All the calcereous corals have a microcrystalline calcite structure. A fossil coral is more properly termed 'agatised', i.e. very largely the CaCO3 has been replaced by SiO2.

Tests:

1. Hot needle test on some inconspicuous part. Needle should be near white-hot. Will go through plastic like a knife through butter and with a burning smell. Rules out all plastic imitations.

2. Acid test. Weak HCl or even vinegar with react (foaming) in contact with an untreated calcereous coral.

3. Acetone test. On an inconspicuous part, rub vigourously with a white cotton swab dripping wet with acetone. Unless the surface has been resin treated, any dye will stain the white swab.

There is more that can be done but not worth discussing until you have the results from those basic, quick but fundamental tests. Run all three tests on each of your three specimens, report your findings here and we can go further if needed.

22nd Jul 2017 22:08 UTCPaul De Bondt Manager

The central pink one comes from Vanuatu. I have them in all colours possible, all natural.

22nd Jul 2017 22:21 UTCAlfred L. Ostrander

Ashley,

I'm not sure exactly what you meant by saying that Mediterranean and Japanese true red corals are hundreds of years old. Do a google search for Corallium rubrum. You will find that this coral and several related species are still extant.

The Utah red coral is quite old, at least Devonian in age if I remember correctly. This material is replaced by red agate and is fossilized.

As Owen is a rather well respected gemologist, his suggestions about testing you can do is spot on, rather definitive and not difficult to do.

23rd Jul 2017 15:56 UTCOwen Lewis

Paul De Bondt Wrote:

-------------------------------------------------------

> The central pink one comes from Vanuatu. I have

> them in all colours possible, all natural.

Paul,

For clarity, do you mean, for your own specimens:

- Bought as being from Vanuatu?

- Bought in/from a Vanuatu address?

- Self-collected from waters off Vanuatu?

- What are 'all colours possible', assuming all dried and cleaned of the polyps and any detritus?

It's hard to know what to make of your post without the extra info. Thanks.

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