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Improving Mindat.orgFake gold specimen

17th Feb 2016 21:56 UTCReiner Mielke Expert

http://www.mindat.org/photo-732199.html why is this even in Mindat? Maybe I should upload this as even more roasted gold?

17th Feb 2016 22:04 UTCAlfredo Petrov Manager

Well, we do have lots of slag minerals photographed on Mindat too. I guess it falls into the category of "geological collectible that isn't a true mineral". To the uploader's credit, he does explain in the photo caption that this is not natural, and explains how it was formed. Lots of collectors are likely to encounter such roasted specimens, so the photo serves an educational purpose.

17th Feb 2016 22:10 UTCReiner Mielke Expert

Well now if that is the case I have some interesting roasted minerals to upload. However slag minerals are not the same, they formed naturally from a man made source, this was formed artifically from a natural source. Maybe we need a section in mindat called fake minerals? Either that, or have a species called Synthetic Gold. Besides how is this different from fake wire silver, sulphur etc? You don't see any of those on Mindat other than maybe this one ( but not noted) http://www.mindat.org/photo-428162.html

17th Feb 2016 22:17 UTCAlfredo Petrov Manager

The more photos of fake minerals we have, the easier it will be for other collectors to learn to recognize them, as long as they are indicated as being fake. But they should probably be placed in the "Other" category, which already has a photo classification for "Fake Minerals", rather than under "Minerals".

17th Feb 2016 23:08 UTCRanger Dave

That's gold, right? How is it fake? Is anything not in it's "natural" state a fake?

17th Feb 2016 23:25 UTCKen Doxsee

I often wonder about elemental mercury specimens and whether they have been "roasted," either naturally or intentionally, to develop more / bigger / or better mercury globules. Not unrelated to the roasted gold debate, perhaps? --Ken

17th Feb 2016 23:29 UTCsteven garza

Dear Ranger;

What Reiner is the SPECIMEN is "fake", not the gold, itself. What is pictured is NOT how the specimen came out of the ground, as; if someone was to try to sell it to you, as being found naturally that way, THEN, it's a fake (as well as a fraud). Before roasting, the gold was tiny inclusions in pyrite or grayish gold bearing sulphosalts, but, the roasting frees the golds, which aggregates into small beads, scattered about the matrix; if it's done skillfully enough, it can look COMPLETELY natural, to the untrained eye.

Your friend, Steve

17th Feb 2016 23:38 UTCBob Harman

I agree with Ranger Dave. In the U.S., gold ore from any of a number of Western mines is processed and refined into those pictured gold bars: 999.9 gold as seen in the pictures. Nothing fake about them. Just refined gold bars that are not usually thought of as a collector mineral specimen, but quite real and genuine in all other respects. It used to be that after refining, the bars were shipped to the national gold depository in Ft. Knox Kentucky. Whether this still happens today, I am not sure, but I do remember the James Bond film, Goldfinger, where Auric Goldfinger, in an elaborate made for the movies plot, attempts to rob the Ft Knox depository.

Some folks on this thread seem a bit too narrow minded. Real and genuine gold bars are just another form of gold from crystallized gold specimens. Other minerals such as silver bars, platinum bars, and various cut colored stones and diamonds also should be similarly accepted onto the Mindat site. Anyone go the big national shows and see an exhibitor case of the mineral specimen along side of a cut and faceted stone? This could easily include a gold specimen along side of a refined ounce of gold.

CHEERS......BOB

17th Feb 2016 23:58 UTCAlfredo Petrov Manager

Ken, grab a piece of cinnabar and do the experiment, before casting aspersions on perfectly good specimens.

As the temperature of decomposition of cinnabar is higher than the boiling point of mercury, I expect that attempts to "sweat" it out of cinnabar would just result in a lot of gaseous mercury fumes, ie the complete loss of the elemental mercury. (But I haven't done the experiment either.)

18th Feb 2016 00:25 UTCRudy Bolona Expert

I read a story a few years ago about fake gold bars, that is, tungsten bars clad with a thin layer of real gold. Since tungsten and gold have very close specific gravities they would not be readily detected in the hand.

18th Feb 2016 00:38 UTCReiner Mielke Expert

Ranger Dave "That's gold, right? How is it fake? Is anything not in it's "natural" state a fake?" It is manmade gold just like synthetic ruby is manmade corundum. It has nothing to do with "natural state" it is how it was created. Anything created by the actions of humans is not natural and is not considered a mineral (according to the latest IMA rules) Yes the specimen shows gold ( manmade) but not the mineral gold ( naturally formed).

18th Feb 2016 01:07 UTCPaul Brandes 🌟 Manager

I'd just like to have a couple of those bars! :-D

18th Feb 2016 01:48 UTCReiner Mielke Expert

Hello Paul,

No problem unless you want them for free or are short on cash or credit ;-)

18th Feb 2016 03:24 UTCRanger Dave

steven garza Wrote:

-------------------------------------------------------

> Dear Ranger;

>

> What Reiner is the SPECIMEN is "fake", not the

> gold, itself. What is pictured is NOT how the

> specimen came out of the ground, as; if someone

> was to try to sell it to you, as being found

> naturally that way, THEN, it's a fake (as well as

> a fraud). Before roasting, the gold was tiny

> inclusions in pyrite or grayish gold bearing

> sulphosalts, but, the roasting frees the golds,

> which aggregates into small beads, scattered about

> the matrix; if it's done skillfully enough, it can

> look COMPLETELY natural, to the untrained eye.

>

> Your friend, Steve

Oh, I see... the quartz crystals I just soaked in IronOut are now fake since that's not how they came out of the ground. And, thanks for the insult in assuming I'm too stupid to know where gold comes from.

18th Feb 2016 03:28 UTCRanger Dave

I agree Bob. That's real gold. Nothing fake about it. Anyone that's graduated from the second grade would know that those bars are not how the gold formed naturally. Nothing is being misrepresented. That gold was not "roasted" either since roasting temperatures are around 350 degrees F and gold melts at 1948 degrees F.

18th Feb 2016 03:32 UTCJolyon Ralph Founder

it should be listed in the 'other' category.

18th Feb 2016 06:34 UTCsteven garza

Dear Ranger;

I'm sorry you assumed I was insulting you, but, since most gold specimens DON'T need any roasting yet are usually HF acid relieved, that are real, your comments seemed to show you didn't understand that difference. Quartz xls soaked in Iron Out (or gold relieved from quartz/calcite matrix) isn't changed in form or structure; they're just considered "cleaned" - the same as if you washed some dirt off a fine quartz cluster.

Your friend, Steve

18th Feb 2016 09:12 UTCErik Vercammen Expert

Most people think gold is only found in it's native form, but there are goldminerals, of which the tellurides (krennerite, sylvanite,calaverite) are the most abundant. The old miners roasted those minerals:for at low temperatures the tellurium is driven off (not healthy to do it) and they could judge if they found gold (that stayed on the matrix). Some of these roasted specimens are still in existence,and a few of them (with the right caption!) should be in Mindat: it is a part of the history of mining and ore geology, and it aids at distuingish real native gold from the goldtellurides (that have also a metallic lustre and 'golden' color).

18th Feb 2016 12:26 UTCUwe Kolitsch Manager

Moved to "Other" category.

18th Feb 2016 13:24 UTCJohn Collins

Interesting discussion all around.

In my mineral collection, all specimens are as they came out of a mine or out of the ground by my hands. There are no faceted gem minerals nor smelted metals. The only exceptions are my polished agates and schalenblende.

That said, I would not turn away any samples of gold bars but they would be stored elsewhere until converted into a cache of cash.

Regards,

John

18th Feb 2016 14:07 UTCLarry Maltby Expert

This thread interested me so I started writing my response. I went into the meaning of “fake” and “fraud” and reworked my words several times to be sure that they weren’t too offensive. I carefully wrote the paragraphs in “word” and spell checked it. I read it again thinking that it was a masterpiece of logic.

When I went to post it I found that the problem was already solved. The photo was placed in the “other” category and was added to the Cripple Creek location page as miscellaneous information. Ah heck, I can’t get a word in edgeways! :-D

18th Feb 2016 15:26 UTCReiner Mielke Expert

If only all problems could be solved so easily.

18th Feb 2016 16:38 UTCRanger Dave

steven garza Wrote:

-------------------------------------------------------

> Dear Ranger;

>

> I'm sorry you assumed I was insulting you,

Such condescension is always intended as an insult and should always be taken as such. Roasting occurs at 350 degrees F. Gold melts much higher so it cannot be "roasted."

18th Feb 2016 22:02 UTCReiner Mielke Expert

"Roasting occurs at 350 degrees F. Gold melts much higher so it cannot be "roasted."" So what do you call this then?

https://en.wikipedia.org/wiki/Roasting_(metallurgy)

18th Feb 2016 23:03 UTCDoug Schonewald

I worked at a smelting complex in Northern Idaho for the better part of 15 years. When they roast ores they reach the plastic stage, not quite molten, but gooey, pliable, and very sticky. The temperature probably exceeds 650 C since the "roast" is bright orange red. The idea is to created 'cinders' so that the ores melts better in a larger furnace, and to utilize various ores to achieve a homogenous mix. Our roasting machine was a German invention know as a Lurgi Roaster; completely contained to eliminate as much of the inevitable dust and smoke involved with roasting ores. Mineral-wise roasting is an essential part of the smelting process.

For those that know the processes this is not a tutorial. Many, I think, do not understand this process and hopefully this helps.

19th Feb 2016 00:39 UTCRanger Dave

Reiner Mielke Wrote:

-------------------------------------------------------

> "Roasting occurs at 350 degrees F. Gold melts much

> higher so it cannot be "roasted."" So what do you

> call this then?

Not 'roasted'.

19th Feb 2016 00:56 UTCReiner Mielke Expert

Dear Ranger Dave,

If you don't want to call it roasted that is fine, however everyone else does.

19th Feb 2016 01:19 UTCDon Saathoff Expert

Having been an assayer here in Southern NM for many years I seen a good many "roasted" samples. Maybe they should be called "torched" because what the prospectors would do is use a propane torch just to see if they had something they needed an official report on. The samples were certainly easier to flux & assay!!

Don S.

19th Feb 2016 01:29 UTCReiner Mielke Expert

I'd be happy calling it torched. A propane torch can easily melt gold.

19th Feb 2016 01:35 UTCDon Saathoff Expert

And volatize both Te & S (and, if they weren't careful, some of the Ag also!)

Don S.

19th Feb 2016 06:25 UTCRanger Dave

T. Douglas Schonewald Wrote:

-------------------------------------------------------

> I worked at a smelting complex in Northern Idaho

> for the better part of 15 years. When they roast

> ores they reach the plastic stage, not quite

> molten, but gooey, pliable, and very sticky. The

> temperature probably exceeds 650 C since the

> "roast" is bright orange red. The idea is to

> created 'cinders' so that the ores melts better in

> a larger furnace, and to utilize various ores to

> achieve a homogenous mix. Our roasting machine was

> a German invention know as a Lurgi Roaster;

> completely contained to eliminate as much of the

> inevitable dust and smoke involved with roasting

> ores. Mineral-wise roasting is an essential part

> of the smelting process.

> For those that know the processes this is not a

> tutorial. Many, I think, do not understand this

> process and hopefully this helps.

Which would be fine IF that is the way the term was being used. It was used as a way to disparage any gold that was not in the exact state that it was in when it came out of the ground. They were playing word games, so I just played it back on them. If they want to see real gold as "fake gold" then that's their problem.

19th Feb 2016 13:32 UTCReiner Mielke Expert

"If they want to see real gold as "fake gold" then that's their problem." You seem to forget that you are on a mineralogical website where "gold " is short for native gold, which is a mineral. Gold the element which you are refering to, is not a mineral. Gold ( or anything else) created by whatever means by humans is not a mineral rather a fake mineral, that is a fake of native gold. I hope that clarifies things for you.

19th Feb 2016 13:44 UTCAlan Pribula

For most minerals, the human-created equivalent material is referred to as "synthetic" or "lab-created" or "lab-grown" chalcanthite or emerald or sapphire or whatever mineral. If you used those same adjectives with "gold," people would think that you're an alchemist!

30th Oct 2016 19:45 UTCTimothy Nybo

I'm trying to determine if I have tellurides and other ores(PtAs ect) of gold or just pyrite. Crystal structure, streak, solubility are proving difficult as to similarities. My roasted rock exudes gold material so instead of elimination testing I'm going to stannous testing of dissolved ore solutions.

My questions are these: does pH/temp effect stannous testing, what does it mean if all the color washes out to a slight blue green, does solution color effect the test, do dissolving solutions beside AR effect the test and finally is there an easier way lol...Any advice is welcomed and graciously recieved. Not a lot of useful info in this business due to propritary secrecy but I'm trying to give it back to the people. That is a long road my friends...

31st Oct 2016 11:22 UTCReiner Mielke Expert

To do a wet chemical test for gold mixed with rock or or other minerals is very difficult because of the varying chemistry of the host rock or minerals which can interfere with the test. That elements that interfere need to be removed first and that in itself can be a complicated process. This sort of information is available in old books under the title "Qualitative Chemical Analysis" Also usually the gold content is so low that a concentration method is required. The standard ways of testing for gold are atomic absorption or fire assay and there are lots of books out there on this. If you have a specific grain you want to test for gold you can get that done for $10 with EDS.

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