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John S. White
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Location: Stewartstown, Pennsylvania, USA
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Posted: Sep 28, 2009 09:58 Post subject: Fake coppers from China |
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Fake coppers from China are now appearing on the market. Some were seen by me at the recent Denver Show and at Tucson 2008. The most obvious are those on quartz crystals which resemble the type of quartz seen by the thousands in many Chinese dealer’s stands. The copper is attached to the quartz in such a way that they immediately look phony. The others are a little more realistic-appearing because they are on rock with a green mineral on the surface. These are not glued on, and I do not know how they are made but they are clearly a furnace product. The matrix appeared cooked, even though it is mostly quartz, and there are quartz crystals associated with the copper. The copper is fresh, not oxidized as one would expect. If you examine the matrix with a loupe you can see that the quartz grains appear to be fringed by glass.
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garchin
Joined: 09 May 2009
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Location: Amsterdam
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Posted: Sep 28, 2009 10:24 Post subject: Re: Fake coppers from China |
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OMY, quelle horreur!
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Peter Megaw
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Location: Tucson, Arizona
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Posted: Sep 28, 2009 11:12 Post subject: Re: Fake coppers from China |
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I looked at these with John. The copper flowers certainly look added to the matrix, although in a few cases it looks like someone figured out how to get the copper to "root" into the matrix. The material on crystals is laughable and reminds me of a gold fake I picked up somewhere that has freestanding "native gold" on both crystal faces and fresh conchoidal fracture surfaces.
It is the matrix that caught my attention...it appears to be partially devitified highly siliceous glass...probably slag. The majority of the vesicles are completely filled with quartz, but some vesicles contain fairly robust limpid quartz crystals that clearly grew in place. I have seen a lot of pyrogenic pyroxenes and other "mafic" crystals in slags, and plenty of quartz crystals in natural devitrified rhyolitic glass, but have never seen what appears to be pyrogenic quartz. The majority are fully formed with no hint of vapor phase hopper growth irregularities, which one might expect in a slag or smelter stack environment...which is where this style of copper flowers often grow. The bulk of the matrix is clear glassy to cloudy partially devitrified/hyrdatedwith copper oxide staining that appears to be weeping from dark spots within the matrix....suggesting that these may be products of the same industrial process. Any slag "mineral" collectors ever seen such a thing?
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alfredo
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Posted: Sep 28, 2009 11:18 Post subject: Re: Fake coppers from China |
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Perhaps electrolytically grown?
I doubt they come from a furnace - the heat would probably destroy the matrix specimen. If I were to try to duplicate such a fake, I'd drill a little pit into the rock or quartz crystal, glue a fragment of metal into it, attach an insulated wire to the metal spot and immerse the whole into a copper sulphate electrolytic bath. Break off insulated wire when done. Look for remains of wire attachment spot at base of copper growths, at contact with matrix.
Can't say for sure this is how it was done; just a suspicion. If that is indeed the case, we might start seeing gold, silver, nickel, chromium, etc, in similar specimens.
(I just saw Peter's post - He beat me to it. I haven't personally looked at the matrix and just assumed they were natural rock. If slag, then perhaps drops of copper were naturally present in the slag matrix and would form an ideal point for initiating later electrolytic growth.)
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Ed Huskinson
Joined: 15 Apr 2009
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Location: Kingman, Arizona
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Posted: Sep 28, 2009 11:24 Post subject: Re: Fake coppers from China |
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John 'n Pete.
Haven't seen them yet, but they look intriguing. Regardless of origin, I'll probably pick one up for my suite of "fakes".
Pete, the fake gold that you mention: is it one of those from Mesquital de Oro? Real light-colored rhyolitic matrix with brownish FeOx overprint, globs of gold all over? Some people have said that they are tellurides that have been roasted. I'm dubious.
Just curious.
Ed
So I'm dubious and curious tambien.
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Peter Megaw
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Posted: Sep 28, 2009 11:29 Post subject: Re: Fake coppers from China |
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Ed...the fake I mentioned is on what looks like a broken piece of pure, limpid Arkasas quartz....probably gobbed with bits of crumpled gilt.
I have a piece of the Mesquital material as well and I agree it does not look roasted, but rather "augmented" with molten gold splashed on to a visible-gold bearing matrix. The roasted tellurides I have seen tend to form little steep-sided globules rather than these splashes.
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Peter Megaw
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Posted: Sep 28, 2009 11:40 Post subject: Re: Fake coppers from China |
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Alfredo, it might have been done with a very fine wire, but I looked very carefully (with my Iwamoto) around the base of several of the copper flowers for hints of glue, tool marks from pressing the copper into the matrix, and continuations of the copper into the matrix...I saw none, but was not looking for a fine bit of wire. I suppose it would be possible to grow the flower for a while...fed by the wire...snip off the wire and then hook the electrode to the flower...in turn burying the wire under younger growth.
Seems like a LOT of work for a copper fake, especially since they aren't all that expensive and are clearly so wrong that they are immediately visually improbable as natural specimens.
If we are of suspicious bent of mind, we might consider these a low-cost precusor to doing the same thing with something that actually might fetch real money...like gold of silver grown on a more plausible matrix.
My guess is that a good soak in acetone will reveal the truth.
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Jordi Fabre
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Posted: Sep 28, 2009 11:41 Post subject: Re: Fake coppers from China |
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The German magazine Lapis in its issue of March 2008 already denounced these Coppers that appeared for first time in Tucson 2008. They said that them grown by electrolysis on Quartz, so them aren't glued, but grown electrolytically.
With the permission of Lapis we published a note in the Spanish Forum informing about it -> https://www.foro-minerales.com/forum/viewtopic.php?p=10450#10450
I copy below a photo related, from the German magazine Lapis.
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Photo of a fake Chinese Copper electrolytically grown. Photo from Lapis magazine. |
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James Catmur
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Posted: Sep 28, 2009 12:14 Post subject: Re: Fake coppers from China |
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I used to work with electrolysis years ago and they look very similar to the things we used to grow on the edge of the baths. So that would be my bet! I just wonder how they attached them to the matrix/quartz.
James
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chris
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Posted: Sep 28, 2009 13:26 Post subject: Re: Fake coppers from China |
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Hi James,
Maybe one guess : you drill small holes in the matrix, then put some small nails inside, then wire them to a battery...
Christophe
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chen
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Posted: Feb 03, 2010 09:48 Post subject: Re: Fake coppers from China |
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it's really have copper growing on matrix,but small size. i saw many such mineral before.
in all,copper and the matrix are nature, just the big copper was glued, fake.
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John S. White
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Posted: Feb 15, 2010 05:51 Post subject: Re: Fake coppers from China |
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Now that I am home again it is easier to respond to the last comment by Chen. I disagree completely with what he has stated. The large cluster of copper is not glued or otherwise attached to the matrix by hand, it has been grown there using some process (perhaps electrolysis), and the same is true of the small specks of copper scattered about the specimen. Examination of the matrix also reveals that the quartz has been exposed to high heat as it is granulated or fused all along its grain boundaries. Very little of this type of specimen is natural, if in fact any of it is natural.
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John S. White
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Posted: Feb 27, 2010 06:13 Post subject: Re: Fake coppers from China |
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It has taken a while but I have now been able to acquire some native coppers from China that are not fakes. The locality information for these is not satisfactory, on the border between Guizhou and Yunnan Provinces, but I am hopeful that more details will be forthcoming. In any case I have examined five of these pieces and I am convinced that they are natural. They also are very different from the obvious fakes shown in the photos in earlier postings on this thread. These coppers occur in altered basalts and appear natural in all respects.
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