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!
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."
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!
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)
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DEN2007-8freibergsilver.jpg [ 61.62 KiB | Viewed 1287 times ]
sorry, I never heard about "German Block" till now. Do you mean reconstructed, finely ground, epoxy glued Azurite-Malachite? According to CIBJO = "reconstruced stones"?
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: 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....
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.
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