We use cookies to show content based on your preferences. If you continue to browse you accept their use and installation. More information. >

FMF - Friends of Minerals Forum, discussion and message board
The place to share your mineralogical experiences


Spanish message board






Newest topics and users posts
28 Mar-09:37:50 Re: 2 unknowns co-occurring with caledonite, grand reef mine, az (Cfrench58)
27 Mar-19:47:08 Re: 2 unknowns co-occurring with caledonite, grand reef mine, az (Pete Richards)
27 Mar-16:15:44 Re: 2 unknowns co-occurring with caledonite, grand reef mine, az (Cfrench58)
27 Mar-15:18:59 Re: 2 unknowns co-occurring with caledonite, grand reef mine, az (Alfredo)
27 Mar-14:39:29 2 unknowns co-occurring with caledonite, grand reef mine, az (Cfrench58)
27 Mar-05:21:48 Re: the mim museum in beirut, lebanon (Mim Museum)
27 Mar-05:03:26 Re: trying to find information on rose/pink quartz and tourmaline associations. (Ning)
27 Mar-02:39:50 Re: the mim museum in beirut, lebanon (Tobi)
27 Mar-00:23:28 Re: collection of volkmar stingl (Volkmar Stingl)
26 Mar-00:53:41 Re: collection of volkmar stingl (Volkmar Stingl)
25 Mar-13:32:10 Re: collection of michael shaw (Michael Shaw)
25 Mar-00:25:58 The mizunaka collection - quartz (Am Mizunaka)
23 Mar-13:35:22 Re: collection of firmo espinar (Firmo Espinar)
22 Mar-08:32:28 Re: collection of michael shaw (Michael Shaw)
22 Mar-04:20:41 Re: the mim museum in beirut, lebanon (Mim Museum)
21 Mar-22:49:19 Re: green seam. Looks like it in a state of decay. (Ning)
21 Mar-22:47:40 Re: green seam. Looks like it in a state of decay. (Ning)
21 Mar-22:45:25 Re: green seam. Looks like it in a state of decay. (Ning)
21 Mar-15:34:23 Re: the mizunaka collection - quartz (Am Mizunaka)
21 Mar-14:35:08 Re: jim’s mineral collection (Jim Wilkinson)
21 Mar-14:15:36 The 4th phoenix heritage mineral show (phms) hosted by mineralogical society of arizona (m (Chris Whitney-smith)
21 Mar-04:36:10 Re: the mizunaka collection (Tobi)
21 Mar-04:11:47 Re: jim’s mineral collection (James Catmur)
20 Mar-23:34:15 The mizunaka collection - quartz (Am Mizunaka)
20 Mar-18:13:16 Re: jim’s mineral collection (Jim Wilkinson)

For lists of newest topics and postings click here


RSS RSS

View unanswered posts

Why and how to register

Index Index
 FAQFAQ RegisterRegister  Log inLog in
 {Forgotten your password?}Forgotten your password?  

Like
111802


The time now is Mar 28, 2024 16:23

Search for a textSearch for a text   

A general guide for using the Forum with some rules and tips
The information provided within this Forum about localities is only given to allow reference to them. Any visit to any of the localities requires you to obtain full permission and relevant information prior to your visit. FMF is strictly against any illicit activities related to collecting minerals.
Oddities from Brandberg, Namibia
  Goto page 1, 2, 3, 4  Next
  Index -> Minerals and Mineralogy
Like
29


View previous topic :: View next topic  
Author Message

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 23, 2014 13:53    Post subject: Oddities from Brandberg, Namibia  

While cleaning crystals, I noted one damaged crystal with a most unusual included crystal. I assume, that as I have never seen something like this from Brandberg before, it must be a rarity from this area, especially the size. There are no similar crystals included. The 'unknown' crystal appears to be square (more flat than square). Any ideas would be welcome.


P1280071.JPG
 Description:
Quartz with unknown inclusion.
Brandberg, Namibia
59 x 31 x 29 mm
The included crystal is approx. 15 mm long
 Viewed:  41393 Time(s)

P1280071.JPG



P1280072.JPG
 Description:
Quartz with unknown inclusion.
Brandberg, Namibia
59 x 31 x 29 mm
 Viewed:  41429 Time(s)

P1280072.JPG



P1280074.JPG
 Description:
Quartz with unknown inclusion.
Brandberg, Namibia
59 x 31 x 29 mm
Photo taken in artificial light.
 Viewed:  41429 Time(s)

P1280074.JPG



P1280061.JPG
 Description:
Unknown crystal
Brandberg, Namibia
Approx. 15 mm long
 Viewed:  41421 Time(s)

P1280061.JPG



P1280063.JPG
 Description:
Unknown crystal
Brandberg, Namibia
Approx. 15 mm long
Same as above
 Viewed:  41430 Time(s)

P1280063.JPG



P1280066.JPG
 Description:
Unknown crystal
Brandberg, Namibia
Approx. 15 mm long
Last 3 photos taken in sunlight.
 Viewed:  41387 Time(s)

P1280066.JPG



_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

cascaillou




Joined: 27 Nov 2011
Posts: 250

View user's profile

Send private message

PostPosted: Feb 23, 2014 18:09    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

such inclusions have been reported in alpine quartz crystals, but their exact nature often remained uncertain. It was suggested that they were possibly anhydrite or scapolite, that was either pseudomorphosed (for instance by muscovite), or dissolved to leave a hollow tube (which might be stained by a thin inner coating)
Back to top
Reply to topic Reply with quote
Like
   

marvsT/Nminerals




Joined: 06 Nov 2008
Posts: 68
Location: Juda, Wisconsin

View user's profile

Send private message

PostPosted: Feb 24, 2014 00:32    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Do you know what other associated minerals came out of that pocket or nearby pockets? The associated minerals might give you a clue as to the mineralogy of the immediate area. Marv
_________________
Member: Badger Lapidary and Geological Society
Great things can be found in small packages!
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 01:17    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

cascaillou wrote:
such inclusions have been reported in alpine quartz crystals, but their exact nature often remained uncertain. It was suggested that they were possibly anhydrite or scapolite, that was either pseudomorphosed (for instance by muscovite), or dissolved to leave a hollow tube (which might be stained by a thin inner coating)


Hi Cascaillou. I also considered the possibility that the original crystal dissolved and left a perfect cavity which in turn was filled with another mineral, possibly even clay. The small black bits of mineral could be either hematite or even epidote (more likely the first). This appears to be sitting directly on the surface of the strange included crystal.

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 01:25    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

marvsT/Nminerals wrote:
Do you know what other associated minerals came out of that pocket or nearby pockets? The associated minerals might give you a clue as to the mineralogy of the immediate area. Marv


Hi Marv. The associated minerals common to this direct area are feldspar,calcite, prehnite, epidote, analcime, hematite(mostly as small inclusions). There are also other minerals but these are uncommon. Somewhere, I have a quartz crystal or two from this area that has a few small yellowish needle like inclusions. I must search for them; perhaps there is a link between the two.

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 01:37    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

See a list of minerals from Mindat. https://www.mindat.org/loc-4534.html

The mineral specimens from Goboboseb rarely has more than 4 of these attached. The most common is calcite, prehnite, feldspar, epidote and analcime. Inclusions are usually small flakes of hematite, minute epidote crystals, or minute prehnite crystals.

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Carles Curto




Joined: 14 Sep 2006
Posts: 160
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 01:56    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

could it be metallic?
Back to top
Reply to topic Reply with quote
Like
   

Carles Curto




Joined: 14 Sep 2006
Posts: 160
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 02:08    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Very probably it is anhydrite. It has been cited, as inclusion, in some Swiss quartzes.
As example, you can see pages 140-142 of the book: Hyrsl, J., Niedermayr, G. 2003. Magic world: inclusions in quartz. Bode Verlag.
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 02:27    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Carles Curto wrote:
Very probably it is anhydrite. It has been cited, as inclusion, in some Swiss quartzes.
As example, you can see pages 140-142 of the book: Hyrsl, J., Niedermayr, G. 2003. Magic world: inclusions in quartz. Bode Verlag.

Hi Carles. Cascaillou shares your thoughts 'such inclusions have been reported in alpine quartz crystals, but their exact nature often remained uncertain'. Can this book be viewed on line? If indeed, do you have a link.? I see anydrite is the dehydrated form of Gypsum. This could easily dissolve, espescially if the one end is open (which is the case here). The cavity can then be filled. However way you look at it, it is a very unusual occurance at Goboboseb.

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Carles Curto




Joined: 14 Sep 2006
Posts: 160
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 03:51    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

I don't know if the book is on line (I suppose not).

Anhydrite, even considering it, genetically, a dehydrated form of gypsum, is a different species, with a very different structure (orthorhombic, very frequently with pseudotetragonal shape). I don't really know if, in your case, you have anhydrite crystals, empty geometric channels or a complete substitution by another mineral. (in fact we don't know if it is really anhydrite).

to be clearer, I add some images and the complete English text (the book was published in German-English) of Hyrsl and Niedermayr.

I hope Jaroslav and Gerhard excuse me the use of these images.



anhydrite010.jpg
 Description:
Brazil. 2,5 cm. (inclusion)
 Viewed:  41249 Time(s)

anhydrite010.jpg



anhydrite011.jpg
 Description:
St. Gottard, Switzerland. 1.cm (edge)
 Viewed:  41194 Time(s)

anhydrite011.jpg



anhydrite012.jpg
 Description:
Lubudi, Congo
2 cm.
(a detail of the published image.
 Viewed:  41238 Time(s)

anhydrite012.jpg



anhydrite014.jpg
 Description:
 Viewed:  41200 Time(s)

anhydrite014.jpg



anhydrite015.jpg
 Description:
 Viewed:  41217 Time(s)

anhydrite015.jpg



anhydrite016.jpg
 Description:
 Viewed:  41268 Time(s)

anhydrite016.jpg


Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 04:18    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Carles Curto wrote:
I don't know if the book is on line (I suppose not).

Anhydrite, even considering it, genetically, a dehydrated form of gypsum, is a different species, with a very different structure (orthorhombic, very frequently with pseudotetragonal shape). I don't really know if, in your case, you have anhydrite crystals, empty geometric channels or a complete substitution by another mineral. (in fact we don't know if it is really anhydrite).

to be clearer, I add some images and the complete English text (the book was published in German-English) of Hyrsl and Niedermayr.

I hope Jaroslav and Gerhard excuse me the use of these images.


Fantastic information Carles. Thank you very much. In this case the void appears to be filled with clay. What an unusual occurance, especially from Brandberg (Goboboseb area)

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

cascaillou




Joined: 27 Nov 2011
Posts: 250

View user's profile

Send private message

PostPosted: Feb 24, 2014 04:33    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

My data is also from the same book.
At the beginning of the book (in the part dealing about fluid inclusions and hollow cavities), there's another paragraph about those tubes. It is explained that while anhydrite and scapolite have been idntified as inclusions in quartz, the nature of these hollow tubes wasn't confirmed for sure, but hypothesized to be anhydrite or scapolite casts (after dissolution)
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 04:53    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

cascaillou wrote:
My data is also from the same book.
At the beginning of the book (in the part dealing about fluid inclusions and hollow cavities), there's another paragraph about those tubes. It is explained that while anhydrite and scapolite have been idntified as inclusions in quartz, the nature of these hollow tubes wasn't confirmed for sure, but hypothesized to be anhydrite or scapolite casts (after dissolution)


Thanks Cascaillou. Any more info will be welcome.

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Debbie Woolf




Joined: 09 Feb 2009
Posts: 168
Location: Kent


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 07:11    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Hi Pierre

I've never seen anything like that in the crystals from the Goboboseb & I've looked at 1000s with a loupe, I get mesmerized by the inclusions :0) I've never seen Prehnite included either.

Nice crystal & a keeper.
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 07:33    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Debbie Woolf wrote:
Hi Pierre

I've never seen anything like that in the crystals from the Goboboseb & I've looked at 1000s with a loupe, I get mesmerized by the inclusions :0) I've never seen Prehnite included either.

Nice crystal & a keeper.


Hi Debbie. This year has been a mad one, I would love to sit down some day and add to the thread on quartz inclusions. I hope to photograph some prehnite inclusions as well. My favourite is the perfect negative crystals. How they form is an absolute mystery. Thanks for your input:-)

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Debbie Woolf




Joined: 09 Feb 2009
Posts: 168
Location: Kent


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 24, 2014 08:20    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

I look forward to seeing the photos someday.
Back to top
Reply to topic Reply with quote
Like
   

cascaillou




Joined: 27 Nov 2011
Posts: 250

View user's profile

Send private message

PostPosted: Feb 24, 2014 14:50    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Pierre, if you're interested in inclusions you will like:

Magic World: Inclusions in Quartz (by Jaroslav Hyrsl and Gerhard Niedermayr)
This book is only about inclusions in quartz

Photoatlas of Inclusions in Gemstones, 3 volumes (by Eduard J. Gubelin and John I. Koivula)
All three volumes are excellent, and each of these cover all kind of inclusions found in many different gemstones. But you might be first interested in the second volume which has 124 pages about inclusions in quartz.

The Microworld of Diamonds (by John I. Koivula)
This one is only about inclusions in diamonds

Keep those books in mind for your birthday!
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 25, 2014 00:48    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

cascaillou wrote:
Pierre, if you're interested in inclusions you will like:

Magic World: Inclusions in Quartz (by Jaroslav Hyrsl and Gerhard Niedermayr)
This book is only about inclusions in quartz

Photoatlas of Inclusions in Gemstones, 3 volumes (by Eduard J. Gubelin and John I. Koivula)
All three volumes are excellent, and each of these cover all kind of inclusions found in many different gemstones. But you might be first interested in the second volume which has 124 pages about inclusions in quartz.

The Microworld of Diamonds (by John I. Koivula)
This one is only about inclusions in diamonds

Keep those books in mind for your birthday!


Hi Cascaillou. I am indeed interested in quartz inclusions (very much so). I will join a club just for that. I will keep the books in mind and see if I can order them somewhere Regards:-)

_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Pierre Joubert




Joined: 09 Mar 2012
Posts: 1605
Location: Western Cape


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 20, 2014 05:27    Post subject: Re: Unknown crystal in Brandberg quartz crystal  

Hi Jordi. Is it possible to change the topic of this thread to' Oddities from Brandberg, Namibia'? This will allow me to show a few more different unusual minerals, most of which I do not know the identity of. By voorbaat dank!
_________________
Pierre Joubert


'The tree of silence bears the fruit of peace. '
Back to top
Reply to topic Reply with quote
Like
   

Jordi Fabre
Overall coordinator of the Forum



Joined: 07 Aug 2006
Posts: 4888
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 20, 2014 11:52    Post subject: Re: Oddities from Brandberg, Namibia  

Pierre Joubert wrote:
Hi Jordi. Is it possible to change the topic of this thread to' Oddities from Brandberg, Namibia'? This will allow me to show a few more different unusual minerals, most of which I do not know the identity of. By voorbaat dank!

Done!
Back to top
Reply to topic Reply with quote
Like
   
Display posts from previous:   
   Index -> Minerals and Mineralogy   All times are GMT - 5 Hours
Page 1 of 4
  Goto page 1, 2, 3, 4  Next  

 
Jump to:  
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 vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


All pictures, text, design © Forum FMF 2006-2024


Powered by FMF