January 24 Through February 4—TUCSON, ARIZONA: Annual show
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Thu Mar 28, 2024 4:13 am

All times are UTC - 4 hours




Post new topic Reply to topic  [ 9 posts ] 
Author Message
 Post subject: Lab-grown Azurite?
PostPosted: Tue Jan 30, 2007 10:54 pm 
Offline
New to the Forum or The Quiet Type

Joined: Tue Jan 30, 2007 10:41 pm
Posts: 4
Occasionally I see large gems or even cabs cut from azurite, but I know that even modest size natural crystals of azurite are fairly rare. Are the ones I'm seeing mostly natural crystals, or is there a lab-grown azurite? I've not been able to find any such thing in an extended internet search. Thanks for your help!

TC


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Wed Jan 31, 2007 12:15 am 
Offline
Platinum Member
User avatar

Joined: Fri Feb 24, 2006 1:20 am
Posts: 2756
Location: Southern California, U.S.A.
Hi TC,
Not all azurite occurrences are crystalline. It also forms in masses or vein fillings, often in association with malachite. The image shows a large contour-cut azurite/malachite cab I cut recently from massive natural material from the Copper World Mine in California. Fine quality azurite/malachite is also produced from the copper mines of Arizona and elsewhere.

There is also a man-made product loosely known as "German Block" because it's formed in loaf-like blocks. Anyone familiar with natural material should be able to sight-I.D. the difference but it fools lots of people. So do the "turquoise," "lapis" and other simulants made the same way. On a cruise to Puerto Vallarta a few years ago I noticed that much of the silver jewelry offered by shoreside ventors featured German Block "stones."

Image

_________________
Rick Martin

www.artcutgems.com


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Thu Feb 01, 2007 9:10 pm 
Offline
New to the Forum or The Quiet Type

Joined: Tue Jan 30, 2007 10:41 pm
Posts: 4
Hi Rick,

Thanks for the clarification! Where can I learn more about German block, so that I can avoid them myself? And is that the only kind of azurite replacement, no one grows crystals of it they the way they do rubies, etc? Thanks!

TC


Top
 Profile  
Reply with quote  
 Post subject: Re: Lab-grown Azurite?
PostPosted: Wed Jul 08, 2015 1:50 pm 
Offline
New to the Forum or The Quiet Type

Joined: Wed Jul 08, 2015 7:55 am
Posts: 3
Interesting question for me, living in Morocco, looking for good specimens of minerals among which azurites and being quite aware of the methods they are using in Fez to simulate native silver on matrices, which does reach very higher prices. Difficult to discriminate the authentic from the fake, no glue used to attach the silver to these supposed matrices but fine work on the latter to insert the silver there and high tech processes of smelting to obtain the filaments of silver with their complicate forms. I am referring to specimens of the form of that of the attached photo ("Silver Medusa" From Freiberg, Freiberg District, Erzgebirge, Saxony, Germany. Measures 8 cm by 6.6 cm in size. Ex. Kevin Ward Collection)


Attachments:
DEN2007-8freibergsilver.jpg
DEN2007-8freibergsilver.jpg [ 61.62 KiB | Viewed 1287 times ]
Top
 Profile  
Reply with quote  
 Post subject: Re: Lab-grown Azurite?
PostPosted: Thu Jul 09, 2015 2:18 am 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 26, 2014 8:23 am
Posts: 254
Dear Rick,

sorry, I never heard about "German Block" till now.
Do you mean reconstructed, finely ground, epoxy glued Azurite-Malachite?
According to CIBJO = "reconstruced stones"?


Top
 Profile  
Reply with quote  
 Post subject: Re: Lab-grown Azurite?
PostPosted: Thu Jul 09, 2015 2:27 am 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 26, 2014 8:23 am
Posts: 254
Once more again - I've a question too .... and sorry for to disturb TC's posting.

I think, this stone is reconstructed, isn't it?

Attachment:
Azurit-Malachit rek. Broschstein 40x30mm H 5mm ca 63ct.JPG
Azurit-Malachit rek. Broschstein 40x30mm H 5mm ca 63ct.JPG [ 83.76 KiB | Viewed 1296 times ]


Azurite-Malachite (rec.?) Broochstone 40x30mm H 5mm approx. 63ct


Top
 Profile  
Reply with quote  
 Post subject: Re: Lab-grown Azurite?
PostPosted: Thu Jul 09, 2015 2:40 am 
Offline
Platinum Member
User avatar

Joined: Fri Feb 24, 2006 1:20 am
Posts: 2756
Location: Southern California, U.S.A.
Steinfroilein, exactly -- the block material was reconstructed. I don't know how it got that name except it was manufactured by a man of German extraction in Bangkok.

But I've seen similar material several times in Tucson and got the impression some was made right here in the U.S. Digging into my memory I seem to recall several different makers, some of whom may still offer that product. I recall it popped up everywhere in jewelry hawked by numerous beach sellers when I took a cruise to Mexico several years ago.

I can't ID your cab for certain -- it looks like natural azure-malachite in your image but the hucksters' techniques are always improving.

_________________
Rick Martin

www.artcutgems.com


Top
 Profile  
Reply with quote  
 Post subject: Re: Lab-grown Azurite?
PostPosted: Thu Jul 09, 2015 7:58 am 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 26, 2014 8:23 am
Posts: 254
@Rick: My stone is a very old one. I found it in an old yellowed cachet (stone paper) dated 1975 in the cellar.
I want to take it to a Mineral Fair (Bretten Germany 15th of November) but I'm not sure of reconstructed so I'm not sure of pricing....


Top
 Profile  
Reply with quote  
 Post subject: Re: Lab-grown Azurite?
PostPosted: Thu Jul 09, 2015 8:52 am 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 26, 2014 8:23 am
Posts: 254
Refering to surham's post (that I could read only just at this time) the origin is native wire silver.

Calcium copper silicate occurs to me, maybe some of you knows it as Egyptian blue, a pigment used for thousand of years in the past. This is synthetic too.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 17 guests


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 post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Gemology Style ported to phpBB3 by Christian Bullock