cobalt - lotharmeyerite or koritnigite ?

Hello !

All is in the title :). Thanks





Edited 1 time(s). Last edit at 05/08/2012 09:10AM by Frédéric Hède.

Hi Frédéric,

Possibly Cobaltkoritnigite? Compare here: [www.mindat.org]

Ron

Yes it's exactly that !

But on other post someone siad to me than it's probably erythrite.... Please help me for this identification :).

Frederic,

I noticed this thread after I started a different topic concerning your photographs! See [www.mindat.org]

To me, this is certainly NOT Cobaltlotharmeyerite, and most probably Erythrite. It could also be some other white arsenate such as Picropharmacolite, tinged pink by Co impurity.

I also strongly doubt that it can be Cobaltkoritnigite. Also these two photos [www.mindat.org] and [www.mindat.org] are most probably Erythrites and not Cobaltkoritnigite. True Cobaltkoritnigite shows a different distinct purple-red colour and also different crystal shape, such as in these photos (all from Bou Azzer distr.): [www.mindat.org] [www.mindat.org] [www.mindat.org] [www.mindat.org]

On the other hand, the tiny indistinct reddish-brown micro-xls scattered on Quartz and the grey sulfide, that are visible in several of your photos (most clearly here [www.mindat.org] ), are much more likely to be Cobaltlotharmeyerite.

Lefteris.

Can I also add this is a very good example of why it is a bad idea to add text data, such as mineral names, to your photograph images.

When corrected, these images can not be displayed in the main database.

Text is not a problem for me.. Problem is base where my photo are fixed. On all other website i can change with an external link :). Text modification are easy with photoshop an less with jpeg photo.... I don't work with jpeg or png. In fact some other problem exist too with low quality of photo on mindat. Format is not my format and compression is often bad.

Ok for erythrite but change on your base error too :)

Thanks Lefteris :)


I make modification in next hours.



Edited 1 time(s). Last edit at 05/08/2012 03:53PM by Frédéric Hède.

Picropharmacolite here

I prefer this solution because color are not ever the same pink not ?

and here the same problem : (i take erythrite like this photo....)

same problem



Edited 2 time(s). Last edit at 05/08/2012 03:51PM by Frédéric Hède.

[www.mindat.org]
Concerning this photo, the Sainfeldite ID is probably correct for the central violet-coloured crystals (I don't think it's Cobaltkoritnigite).

Concerning the pink balls, they could be either Erythrite, or Co-bearing Picropharmacolite. I really can't tell here. Association with Sainfeldite implies Picropharmacolite, but of course could also be consistent with Erythrite.

Lefteris.

All modification have been done :). For me, it's important to learn. Thanks for all.

I agree with Lefteris. Will sent messages concerning the two mentioned photos.

hello,

i have written to Ivan (who has sent this specimen to me)

His response : I open personately the geode, extracting 46 samples. I let 2 of them analyze and they both gave a high Mg enought to cosider them wendwilsonite.

=> Mg is enough to spell them wendwilsonite....

I correct now definitively... ;)

Fred



Edited 2 time(s). Last edit at 05/08/2012 07:11PM by Frédéric Hède.

Excellent, this info is precious to add in the photo captions.

By the way, Frederic, these are beautiful photos!!

Lefteris.

Thanks Lefteris ;). And i hope to continue longtimes, it's a great hobby for my old days....

"I let 2 of them analyze and they both gave a high Mg enought to cosider them wendwilsonite."

If the analyses were done by SEM-EDS you have to watch out - Mg and As peaks show a very strong overlap!

I asked about this a long time ago but got no response so I will ask it again. I have a specimen with this [www.mindat.org] directly on top of this [www.mindat.org] Is it common to find two different forms of Erythrite together like this or are the balls something else?

It's not common, but I have seen such two generations of erythrite.

I also have one such piece. I have always assumed that both are Erythrite - just of two different generations.