We use cookies to show content based on your preferences. If you continue to browse you accept their use and installation. More information. >

FMF - Friends of Minerals Forum, discussion and message board
The place to share your mineralogical experiences


Spanish message board






Newest topics and users posts
08 Oct-11:22:30 Re: collection from dany mabillard (Tobi)
08 Oct-03:42:43 Re: collection from dany mabillard (Dany Mabillard)
08 Oct-03:28:22 Re: new generation for picture - ploum (Dany Mabillard)
07 Oct-14:07:22 Re: collection of michael shaw (Tobi)
07 Oct-13:08:41 Re: collection of michael shaw (Michael Shaw)
07 Oct-07:20:44 Re: collection of michael shaw (Tobi)
07 Oct-06:49:36 Re: galena from hiendelaencina - tri-state (James Catmur)
06 Oct-09:21:54 Re: collection of michael shaw (Michael Shaw)
04 Oct-23:37:22 Re: collection of volkmar stingl (Volkmar Stingl)
04 Oct-07:08:00 Re: galena from tri-state (James Catmur)
04 Oct-06:36:13 Re: collection of volkmar stingl (Volkmar Stingl)
04 Oct-03:41:21 Re: galena from hiendelaencina (Tobi)
03 Oct-13:48:58 Collection of carles millan: native bismuth (Carles Millan)
03 Oct-11:10:59 Re: galena from hiendelaencina (James Catmur)
03 Oct-08:21:22 Re: collection of michael shaw (Michael Shaw)
03 Oct-02:09:41 Re: the mim museum in beirut, lebanon (Mim Museum)
02 Oct-22:09:20 Re: collection of volkmar stingl (Volkmar Stingl)
02 Oct-13:50:42 Re: galena from hiendelaencina (Tobi)
02 Oct-13:31:20 Re: galena from hiendelaencina (Michael Shaw)
02 Oct-13:14:16 Re: galena from hiendelaencina (Alfredo)
02 Oct-10:46:52 Re: galena from hiendelaencina (Peter Megaw)
02 Oct-09:25:37 Galena from hiendelaencina (James Catmur)
02 Oct-04:24:13 Re: collection of volkmar stingl (Volkmar Stingl)
02 Oct-03:38:27 Re: collection of volkmar stingl (Carles Millan)
01 Oct-23:23:29 Re: collection of volkmar stingl - something wrong with "like" function? (Volkmar Stingl)

For lists of newest topics and postings click here


RSS RSS

View unanswered posts

Why and how to register

Index Index
 FAQFAQ RegisterRegister  Log inLog in
 {Forgotten your password?}Forgotten your password?  

Like
115671


The time now is Oct 08, 2024 20:35

Search for a textSearch for a text   

A general guide for using the Forum with some rules and tips
The information provided within this Forum about localities is only given to allow reference to them. Any visit to any of the localities requires you to obtain full permission and relevant information prior to your visit. FMF is strictly against any illicit activities related to collecting minerals.
Fake chrysocollas from Congo
  
  Index -> Incorrect classification and fakes
Like
6


View previous topic :: View next topic  
Author Message

FMF Forum
Site Admin



Joined: 21 Dec 2007
Posts: 47
Location: Spain


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Jun 13, 2023 10:19    Post subject: Fake chrysocollas from Congo  

Our friend Christophe Gobin sent us a review to publish in FMF Forum about some supposed malachites and chrysocollas from Congo that have been on the market since last year.

We publish all the information he has provided to us:


Hi all,

We have seen in 2022 some malachite and chrysocolla specimens from the Congo, marketed by some Chinese dealers. I received some of them and I immediately suspected that they were fake.
I am used to travel to the Congo and have been offering a lot of malachite and chrysocolla specimens from this country.

I asked Dr Federico Pezzotta from MCP laboratory in Milano if he could run some analysis. It was a long and tedious scientific study, of about 10 months. He concluded that they are fake. The malachite specimens have undergone a chemical treatment which has made it possible to modify its color in a stable way.
They are real malachites from Congo but it is not chrysocollas. The fake ones marketed by some Chinese dealers must not damage the reputation of the real malachite-chrysocollas that we saw in the past and if it can help some collectors not to be scammed.

So here is his report, it is confirmed they are fake.
Christophe Gobin



Chrysocolla 1.jpg
 Description:
The chrysocolla coating is like a very thin layer on the surface of the malachite like one micron thick. There is no chrysocolla inside the structure of the malachite. In 28 years of Congo, I never saw this kind of structure of chrysocolla just coating the malachite like that.
 Viewed:  20619 Time(s)

Chrysocolla 1.jpg



Chrysocolla 2.jpg
 Description:
 Viewed:  20607 Time(s)

Chrysocolla 2.jpg



Chrysocolla 3.jpg
 Description:
Usually inside the combinations of chrysocolla and malachite specimens, you see the superposition of the layers of the chrysocolla and the malachite like for this old specimen (left).

Some pieces have some damages, and it is blue inside the damage. How is it possible when the thickness of the coating is only a micron or so. Except if we consider that they were damaged before the coating (right).
 Viewed:  20578 Time(s)

Chrysocolla 3.jpg



Chrysocolla analysis 1.jpg
 Description:
 Viewed:  20595 Time(s)

Chrysocolla analysis 1.jpg



Chrysocolla analysis 2.jpg
 Description:
 Viewed:  20572 Time(s)

Chrysocolla analysis 2.jpg



Chrysocolla analysis 3.jpg
 Description:
 Viewed:  20575 Time(s)

Chrysocolla analysis 3.jpg


Back to top
Reply to topic Reply with quote
Like
6
   
Display posts from previous:   
   Index -> Incorrect classification and fakes   All times are GMT - 5 Hours
Page 1 of 1
    

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


All pictures, text, design © Forum FMF 2006-2024


Powered by FMF