Talk pages for photographs http://www.mindat.org/msgboard-106.html Tue, 21 May 2013 18:34:09 +0000 Phorum 5.2.15a http://www.mindat.org/forum.php?read,106,294311,294355#msg-294355 http://www.mindat.org/forum.php?read,106,294311,294355#msg-294355 Chris Stefano Photos Mon, 20 May 2013 20:30:24 +0000 http://www.mindat.org/forum.php?read,106,294311,294353#msg-294353 http://www.mindat.org/forum.php?read,106,294311,294353#msg-294353 Christian Auer Photos Mon, 20 May 2013 19:24:45 +0000 http://www.mindat.org/forum.php?read,106,294311,294311#msg-294311 http://www.mindat.org/forum.php?read,106,294311,294311#msg-294311 www.mindat.org]

This quartz is definitely not from Amstall! Also, the matrix does not look like the marble from there.
Looks very much like one of the black quartzes in anhydrite from Emilia Romagna, Italy to me.
Maybe it was received with a wrong label.]]> Harald Schillhammer Photos Mon, 20 May 2013 05:26:00 +0000 http://www.mindat.org/forum.php?read,106,294203,294231#msg-294231 http://www.mindat.org/forum.php?read,106,294203,294231#msg-294231 Estou a responder a esta questão porque a Biscaia é uma área e não uma pedreira.
Isto porque recolhi à alguns anos umas amostras com turmalina que não são da pedreira que está a representar a Biscaia.
Penso que a Pedreira deveria ter um nome e é só questão de carregar este dado como sub-localidade na Biscaia e fazer a descrição adequada a nivel geológico e mineralógico.

Cumprimentos.

Martins da Pedra]]> António Manuel Ináçio Martins Photos Sun, 19 May 2013 09:00:52 +0000 http://www.mindat.org/forum.php?read,106,294203,294203#msg-294203 http://www.mindat.org/forum.php?read,106,294203,294203#msg-294203
Isto de encontrar sítios porreiros para colher amostras aqui ao pé da capital não está fácil. Consegue-me dizer ao pé de que localidade fica esta antiga pedreira?

André]]> André Gonçalves Photos Sat, 18 May 2013 20:28:58 +0000 http://www.mindat.org/forum.php?read,106,283741,294134#msg-294134 http://www.mindat.org/forum.php?read,106,283741,294134#msg-294134 Dermot
[www.cbc.ca]
P.s. Thanks Maggie]]> Dermot Walsh Photos Fri, 17 May 2013 20:38:44 +0000 http://www.mindat.org/forum.php?read,106,283741,294053#msg-294053 http://www.mindat.org/forum.php?read,106,283741,294053#msg-294053 Maggie Wilson Photos Fri, 17 May 2013 00:03:45 +0000 http://www.mindat.org/forum.php?read,106,283741,294045#msg-294045 http://www.mindat.org/forum.php?read,106,283741,294045#msg-294045 depending upon the black flies. just having a look..any and all advice appreciated..
best
dermot]]> Dermot Walsh Photos Thu, 16 May 2013 22:00:00 +0000 http://www.mindat.org/forum.php?read,106,292438,293217#msg-293217 http://www.mindat.org/forum.php?read,106,292438,293217#msg-293217
If a picture is particularly well liked by the members, then it will register on the "popular" page and gain even more views possibly more uploads to other sites. Over 27000 times in the last few days...? I have no way of knowing, but my guess is not likely.

Hope the tech problem is resolved soon.

M]]> Maggie Wilson Photos Mon, 06 May 2013 10:39:19 +0000 http://www.mindat.org/forum.php?read,106,292438,293182#msg-293182 http://www.mindat.org/forum.php?read,106,292438,293182#msg-293182 Rob Woodside Photos Mon, 06 May 2013 01:05:51 +0000 http://www.mindat.org/forum.php?read,106,292438,293176#msg-293176 http://www.mindat.org/forum.php?read,106,292438,293176#msg-293176
for example [pinterest.com]]]> Maggie Wilson Photos Sun, 05 May 2013 23:06:01 +0000 http://www.mindat.org/forum.php?read,106,292438,293144#msg-293144 http://www.mindat.org/forum.php?read,106,292438,293144#msg-293144
For instance, [www.mindat.org] has been viewed >27000 times in the last days (basically every recent view from the same IP address).]]> Uwe Kolitsch Photos Sun, 05 May 2013 16:04:08 +0000 http://www.mindat.org/forum.php?read,106,292438,293026#msg-293026 http://www.mindat.org/forum.php?read,106,292438,293026#msg-293026 two examples:
[www.mindat.org]
[www.mindat.org]
Something is very wrong in Mindat on photographic representations by more than one author in most localities in Portugal, which reportedly were manipulated after I make a statistic.
I have concluded to have the connivance of the editor about this situation or develops every day thankless job to ensure the ranking of your photos and scanning all them, personally do not believe that because it is unreal.
The list is long and I will give some examples of locations referred this matter:
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org]
[www.mindat.org] - This photo is wrong because is mine
[www.mindat.org]
[www.mindat.org]
I think that with patience or with the help of the editor is possible to verify this situation because the statistic does not lie. For me it was best if the computer program ought to be random in photographic representation on the front page when the location was represented by more one picture or more one author.

Thank´s

Martins da Pedra]]> António Manuel Ináçio Martins Photos Sat, 04 May 2013 09:18:02 +0000 http://www.mindat.org/forum.php?read,106,292878,292895#msg-292895 http://www.mindat.org/forum.php?read,106,292878,292895#msg-292895
The photo has been posted as #423859. I have two views of the sample, one under normal light and the other under a lower light level to emphasize the blue colour of the Halite. As far as I know the Halite occurs as cubic crystals in colourless Sylvite. There has been no investigation of the blue Halite in the Lanigan deposit, as you have done in New Mexico, so I don't know any more details of the occurrence. I did not collect the sample myself as I have only been underground in the Rocanville Mine. The blue Halite samples show up occasionally in Canadian mineral shows, I bought this one in 2006, but they are not common.

Remobilization of the salts in the Saskatchewan potash beds is a method of coarsening the grain size and removing impurities. I saw a 1 meter wide lens of canary-yellow Carnallite in the wall of a stope in the Rocanville Mine when we were there. The grain size of the Carnallite was an order of magnitude larger than the surrounding potash ore and the non-salt clay minerals had not been remobilized. The yellow colour was different than the red colour of Carnallite in the normal potash ore so some of the elements were selectively remobilized. This remobilization was done under pressure as the Carnallite lens forced the bedded layers of potash apart, but did not disrupt them. The texture of the Carnallite within the lens is similar to my sample of Sylvite/Halite from Lanigan and differs from normal potash ore.

Hope this helps,

Richard Gunter]]> Richard Gunter Photos Thu, 02 May 2013 21:51:22 +0000 http://www.mindat.org/forum.php?read,106,292878,292892#msg-292892 http://www.mindat.org/forum.php?read,106,292878,292892#msg-292892
The explanation for the POTD was meant for the halite in the Carlsbad District, not necessarily for all blue halite worldwide. Thanks for the clarification. According to my research, the trigger would be the combination of the free electrons and the Sodium ions, forming sodium metal colloids. There could be remobilization at some point, but I'm not sure that remobilization or recrystallization has to be always necessary for the change of color. The paper that I read this morning on pressure being applied to change color in irradiated halite also stated that artificial light had to be introduced into the process for the halite to turn blue. I'm not sure there would be a light source available if this process was happening naturally. :-)

Do you have a picture of your Lanigan specimen? If so, I would be interested to see it. Is the specimen a cleave or a crystal? If it's a cleave then that could explain the lack of clays since I know of some blue halite crystals that have been over 2 meters wide, and some of the blue/purple color can be present even in the center of these crystals. Did you personally collect the specimen? Why do you believe the halite has been recrystallized/remobilized at some point?

I'm not asking these questions to shed doubt on your point, but I am curious about these other occurences of blue/purple halite worldwide. The more information we can find out about minerals and the processes that formed them, the better. :)-D

Phil]]> Philip Simmons Photos Thu, 02 May 2013 21:17:09 +0000 http://www.mindat.org/forum.php?read,106,292878,292890#msg-292890 http://www.mindat.org/forum.php?read,106,292878,292890#msg-292890
I agree that the Halite and Sylvite have to be intermixed. There just needs to be another trigger, such as pressure, to turn the Halite blue. The Sylvite in all cases where the Halite is blue seems to be colourless. This would indicate some reaction with the Na ions. There are also no clay minerals associated with the blue Halite/Sylvite in the Lanigan sample. This is an indication that the sample is remobilized as clay minerals and often reddish Carnallite are a constant part of normal Saskatchewan potash strata. My comment was directed at the note on the PoD which was definite in its conclusion of the origin of the blue Halite without looking at all of the occurrences of Sylvite and Halite.

Richard Gunter]]> Richard Gunter Photos Thu, 02 May 2013 20:18:25 +0000 http://www.mindat.org/forum.php?read,106,292878,292887#msg-292887 http://www.mindat.org/forum.php?read,106,292878,292887#msg-292887 This is a response I posted a couple months back in answer to a similar question brought up in another thread. I was just reading an article this morning that mentioned lab irradiated halite turning blue when subjected to unconfined pressures of 25,000 - 125,000 pounds per square inch. But, based on my field observations in the Carlsbad District mines (stated below), sylvite HAS to be intimately related to the process that turns the halite blue/purple.

Thanks for the great questions! If you notice in the article I wrote "Halite Coloration Theories" meaning that there are several theories that exist for the blue halite coloring mechanism. The major theory I presented is based on the research I did as well as observations of the environment in which the halite specimens were found.

In the occurence of blue halite at the two mines in which I work, the blue halite is always associated with colorless (or "high-grade") sylvite. I don't know much about the Canadian mines, but the vast majority of sylvite ore we mine in Carlsbad is red to orange, colored by finely divided hematite. In these areas, we never find blue halite unless there is "high-grade" present. Maybe there is something within the hematite included sylvite that inhibits the radiation effect upon surrounding halite? I have also observed many instances where two or more halite crystals are growing together in the high-grade sylvite seams, and when separated, the contact between the two halite crystals is completely colorless, while the surface areas that were in contact with the sylvite were blue to purple. This leads me to believe that the sylvite was in some way a major catalyst for the coloration of the halite. Remember, these are observations based on the occurence of halite in Carlsbad, not other world-wide occurences. I am not familiar enough with other localities to give you an explanation on coloration, especially in areas that contain no sylvite or other source of radiation.

In the article I also address another theory based on the observation you posted above. Since some of these deposits do not have a radiation source readily available, it could be possible that the color is due to the leaching of trace amounts NaBr present within the halite. Per my article (Sonnenfeld, 1995): "The phenomenon appears to be concentrated along paths of circulating brines, saturated for NaCl, that leach, brecciate and recrystallize halite and preferentially dislodge bromine ions from crystal lattices, leaving metallic sodium behind."

FYI - While any one particular coloring mechanism is not fully endorsed by all scientists, most of the research I conducted was in agreement that the metallic sodium colloids are the source of the color.

I hope this adequately answers your questions. If not, we can hash out more of these theories in detail. Like I mention above, there is more than one theory that have their strong and weak points. I chose to cover the radiation theory in the greatest amount of detail because it seems to present the most plausible explanation based on my research and real-time observations. We could also have more than one coloring mechanism, depending on the geology and type of deposit in which the halite is found.

Philip]]> Philip Simmons Photos Thu, 02 May 2013 19:14:51 +0000 http://www.mindat.org/forum.php?read,106,292878,292878#msg-292878 http://www.mindat.org/forum.php?read,106,292878,292878#msg-292878 Richard Gunter Photos Thu, 02 May 2013 16:45:03 +0000 http://www.mindat.org/forum.php?read,106,292769,292769#msg-292769 http://www.mindat.org/forum.php?read,106,292769,292769#msg-292769 Roger Sedgwick Photos Wed, 01 May 2013 03:00:42 +0000 http://www.mindat.org/forum.php?read,106,289304,292540#msg-292540 http://www.mindat.org/forum.php?read,106,289304,292540#msg-292540
Whatever, its an interesting piece and well worth some detailed study.]]> Owen Lewis (2) Photos Mon, 29 Apr 2013 12:34:02 +0000 http://www.mindat.org/forum.php?read,106,289304,292530#msg-292530 http://www.mindat.org/forum.php?read,106,289304,292530#msg-292530 Woody Thompson Photos Mon, 29 Apr 2013 10:27:06 +0000 http://www.mindat.org/forum.php?read,106,292184,292517#msg-292517 http://www.mindat.org/forum.php?read,106,292184,292517#msg-292517 www.vanderkrogt.net]

I confess that this is quite new to me. AFAIK, it is not in use by gemmologists.]]> Owen Lewis (2) Photos Mon, 29 Apr 2013 04:06:39 +0000 http://www.mindat.org/forum.php?read,106,289304,292516#msg-292516 http://www.mindat.org/forum.php?read,106,289304,292516#msg-292516 Wayne Corwin Photos Mon, 29 Apr 2013 03:48:36 +0000 http://www.mindat.org/forum.php?read,106,289304,292484#msg-292484 http://www.mindat.org/forum.php?read,106,289304,292484#msg-292484 Pavel Kartashov Photos Sun, 28 Apr 2013 19:57:06 +0000 http://www.mindat.org/forum.php?read,106,292184,292483#msg-292483 http://www.mindat.org/forum.php?read,106,292184,292483#msg-292483 Pavel Kartashov Photos Sun, 28 Apr 2013 19:52:41 +0000 http://www.mindat.org/forum.php?read,106,292438,292467#msg-292467 http://www.mindat.org/forum.php?read,106,292438,292467#msg-292467 Uwe Kolitsch Photos Sun, 28 Apr 2013 17:29:44 +0000 http://www.mindat.org/forum.php?read,106,292438,292466#msg-292466 http://www.mindat.org/forum.php?read,106,292438,292466#msg-292466 www.mindat.org]]]> Rui Nunes Photos Sun, 28 Apr 2013 17:21:05 +0000 http://www.mindat.org/forum.php?read,106,292438,292452#msg-292452 http://www.mindat.org/forum.php?read,106,292438,292452#msg-292452 Uwe Kolitsch Photos Sun, 28 Apr 2013 13:59:47 +0000 http://www.mindat.org/forum.php?read,106,292438,292438#msg-292438 http://www.mindat.org/forum.php?read,106,292438,292438#msg-292438 It Is not a correct atitute, isn't it?
This happens too often and demonstrates a total lack of decency...]]> Rui Nunes Photos Sun, 28 Apr 2013 08:35:07 +0000 http://www.mindat.org/forum.php?read,106,292184,292351#msg-292351 http://www.mindat.org/forum.php?read,106,292184,292351#msg-292351 Ralph Bottrill Photos Fri, 26 Apr 2013 23:26:45 +0000