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Fakes & Frauds"fake" stalactitic realgar from china

29th Jun 2010 15:00 UTCJolyon Ralph Founder

Now, I can't be certain this is fake, but it looks unnaturally unnatural, like a lump of molten gunk. It does look to be realgar, but I wonder if it's possible to melt realgar and let it solidify as this sort of stuff?

Unless, of course, this really is natural.

From China, of course. size approx 10cm across.

Anyone seen it before?

29th Jun 2010 16:57 UTCAlfredo Petrov Manager

Does look suspicious, I agree. Melted realgar does occur naturally, in small specimens, often labelled "jeromite". Sulphur and arsenic sulphide glasses are miscible in any proportion, i think, and that has given rise to several amorphous mineraloid names, like jeromite, arsensulfurite, etc. These occur both as mine fire products and natural volcanic products.

This particular Chinese piece looks more like melted sulphur than melted realgar.

29th Jun 2010 17:03 UTCJolyon Ralph Founder

The piece was relatively heavy, and had the right metallic sheen (especially on the broken surfaces) that I was reasonably confident that it was arsenic sulphide.

29th Jun 2010 17:40 UTCRob Woodside 🌟 Manager

Does it have the concoidal fracture of glass? It looks like an As glass.

29th Jun 2010 17:54 UTCLuís Martins 🌟

I've bought a sample like the one you pictured here, and it's hollow, so I think it's natural... Can't see any indication that it's a fake...

29th Jun 2010 18:00 UTCJolyon Ralph Founder

Rob:

I don't remember it being so. I'll see if I can get a picture of the end

Luis:

I don't understand how being hollow makes it more likely to be natural?

29th Jun 2010 18:20 UTCRob Woodside 🌟 Manager

Even if it is a glass there is the question of its geologic origin. Without matrix, I'm not sure you can tell.

29th Jun 2010 22:13 UTCLuís Martins 🌟

Jolyon, it doesn't :) But, looking at the specimen closely, I can't see any indication of it being faked, like any strange, non natural looking material, or any marks of a matrix that was later removed, just to provide a place for the specimen to grow on... When I first saw those specimens, which were common 2 years ago in the very few shows that we have here in Portugal, I taught the specimens were strange looking, almost unnatural, but since I didn´t saw anything that could indicate that they were fake, I believed the dealers... Also, those specimens were very cheap, about 20€ a 15cm piece, so even they were fake it didn't make them an expensive mistake (:D

30th Jun 2010 12:52 UTCJolyon Ralph Founder

Here's the base (thanks Ida for the photo)

Doesn't look like S/As glass to me!

30th Jun 2010 15:11 UTCAlfredo Petrov Manager

At Tucson, did you see Jaroslav Hyrsl's melted-looking orpiments from Peru? Greenish yellow, but weird stuff, like this.

30th Jun 2010 19:02 UTCRob Woodside 🌟 Manager

As you say that's not an As glass. What is it? Is the black Duranusite?

I gave a piece of Jaroslav Hyrsl's orpiment to RRUFF and they posted it as realgar!!! See: http://rruff.info/realgar/display=default/R100026

I don't even remember if there were insignificant red xls on it. Most of the piece was botryoidal green with concoidal fracture. I'm pretty sure it is an As glass and had seen similar from Baia Mare.

7th Jul 2010 15:26 UTCJolyon Ralph Founder

So. noone seems to want to commit to whether this is genuine or not. Needs further work I think!

Jolyon

7th Jul 2010 15:35 UTCAlfredo Petrov Manager

Well, knowing the chemical composition would certainly help. And an XRD to find out whether it's crystalline or a glass.

7th Jul 2010 15:59 UTCTREILLARD Michel

Do not it'll be a metamorphosis? Regard's. Michel

9th Jul 2010 14:32 UTCNoah Horwitz

Maybe also check for arsenolite on the surface, which could indicate that the specimen was heated (by people, mine fire, geological processes...). The little glints of light from the unbroken surface make it look microcrystalline.

20th Mar 2011 21:28 UTCRémi Bornet

Hello !

In France we have specimens that look like your Chinese sample... (La Ricamarie Mine, Saint-Etienne, Loire, Rhône-Alpes, France) These realgars come from a burning coal mine that explain the stalactitic morphology.

http://www.le-comptoir-geologique.com/realgar-ricamarie/bv000055.jpg

9 x 5 x 5 cm

Best regards,

Rémi BORNET

21st Mar 2011 18:31 UTCRob Woodside 🌟 Manager

Thanks Rémi. That looks like what I was calling a sulfide glass. It turns out that the "orpiment" from Palomo is not a sulfide glass, but a new mineral. You may have found more, though the Palomo material was more green.

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