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
24 Oct-23:42:01 Re: collection of volkmar stingl (Volkmar Stingl)
24 Oct-21:41:08 Re: don lum collection (Don Lum)
24 Oct-21:40:15 Re: the mizunaka collection - quartz (Am Mizunaka)
24 Oct-20:05:46 Silvia's collection - huge siderite (Silvia)
24 Oct-19:57:24 Re: the mizunaka collection - quartz (Silvia)
24 Oct-18:44:45 The mizunaka collection - quartz (Am Mizunaka)
24 Oct-15:15:23 Re: collection of sante celiberti (Sante Celiberti)
24 Oct-14:52:30 Re: collection of michael shaw (Michael Shaw)
24 Oct-13:43:08 Re: collection of michael shaw (Silvia)
24 Oct-11:17:10 Re: collection of michael shaw (Michael Shaw)
24 Oct-09:37:12 Re: collection of volkmar stingl (Volkmar Stingl)
24 Oct-09:28:16 Re: collection of michael shaw (Volkmar Stingl)
24 Oct-09:04:01 Re: collection of michael shaw (Michael Shaw)
24 Oct-03:54:43 Re: collection of tobi (Dany Mabillard)
24 Oct-03:50:24 Re: collection of tobi (Tobi)
23 Oct-23:28:11 Re: help found with items (Philippe Durand)
23 Oct-15:08:16 Silvia's collection - classic portugese ferberite (Silvia)
23 Oct-13:59:45 Re: help found with items (Lou B.)
23 Oct-13:56:06 Help found with items (Lou B.)
23 Oct-13:45:52 Re: collection of tobi (Tobi)
23 Oct-12:29:41 Re: munich show (mineralientage) 2021 (Jordi Fabre)
23 Oct-12:23:20 Munich show (mineralientage) 2021 - like a new show (Jordi Fabre)
23 Oct-11:54:58 Re: collection of tobi (Tobi)
23 Oct-09:31:25 Re: munich show (mineralientage) 2021 (James Catmur)
23 Oct-04:07:52 Re: new generation for picture - ploum (Ploum)

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
85979


The time now is Oct 24, 2021 23:47

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.
Ajoite From Messina
  
  Index -> Minerals and Mineralogy
Like
5


View previous topic :: View next topic  
Author Message

Roger Warin




Joined: 23 Jan 2013
Posts: 1013


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Aug 27, 2021 13:39    Post subject: Ajoite From Messina  

Hello,
I have a question: is there a solid solution of ajoite?
FOV : Quartz crystal width = 55 mm.
In my photo, we see the ajoite fibers discolouring, as if there was a loss of copper.

K3Cu2+20Al3Si29O76(OH)16 · 8H2O
Triclinic 1 or -1 ? No wonder with such a formula.
Thank you.



Ajoite_20149_R.jpg
 Mineral: Ajoite
 Locality:
Messina Mine, Musina (Messina), Vhembe District, Limpopo Province, South Africa
 Dimensions: width 55 mm
 Description:
 Viewed:  587 Time(s)

Ajoite_20149_R.jpg


Back to top
Reply to topic Reply with quote
Like
3
   

Peter Megaw
Site Admin



Joined: 13 Jan 2007
Posts: 925
Location: Tucson, Arizona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Aug 27, 2021 16:56    Post subject: Re: Ajoite From Messina  

Roger, Ajoite is famous for "deteriorating" into chrysocolla, so my first guess would be that that's what you're seeing rather than a compositional shift within an ajoite-XXX series. (yes, I realize changing to chrysocolla is a compositional shift). As I remember, historically there were questions about ajoite even being a valid species because it was so hard to get a decent pattern off of things identified as ajoite. This deterioration was well developed in the recent finds of ajoite from Rancho Jacalito, Sonora, Mexico...only a small percentage of what got analyzed was still ajoite.
_________________
Siempre Adelante!
Back to top
Reply to topic Reply with quote
Like
2
   

Roger Warin




Joined: 23 Jan 2013
Posts: 1013


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Aug 27, 2021 21:29    Post subject: Re: Ajoite From Messina  

Thank you very much Peter,
The chemical formula makes me uncomfortable (I'm just a chemist).
Another fact surprises me in my photo, it is the alternation of blue and white shades.
I therefore readily agree with your answer, especially since the origin seems to me to be hydrothermal in nature.
The structure (AMS-data: Pluth J J, Smith J V - 2002) is obviously complex but seems ordered.
However, along the "a" axis, this unit cell surprises me a lot.
I'm asking myself a neophyte question, isn't it a semi-crystalline structure, as we find in some polymers?
The crystalline germs could be spherulites.
A thin section would highlight the Extinction Crosses of Malta, in XPol).
Excuse my curiosity.



Ajoite-AMS-data.jpg
 Description:
 Viewed:  491 Time(s)

Ajoite-AMS-data.jpg


Back to top
Reply to topic Reply with quote
Like
   

Roger Warin




Joined: 23 Jan 2013
Posts: 1013


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Aug 27, 2021 22:45    Post subject: Re: Ajoite From Messina  

Hello,
This photo is taken with a binocular (8X).
Difficult focusing, stacking of 33 shots.
We cannot say that they are rectilinear needle-like crystals.
The deposit of ajoite takes place during a first stop of the crystallization of quartz (or during a slowing down).
Then the quartz resumes its growth.
The aggregate of ajoite is found incorporated into a kind of silica gel before it crystallizes, it seems to me. We would thus have this formation of space shaeves.
What do you think ?



Ajoite#1-01-AB-1_R.jpg
 Mineral: Ajoite
 Locality:
Messina Mine, Musina (Messina), Vhembe District, Limpopo Province, South Africa
 Description:
 Viewed:  480 Time(s)

Ajoite#1-01-AB-1_R.jpg


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 1
    

 
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 2006-2021


Powered by FMF