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

FMF English Forum is moderated by John S. White and Peter Megaw
 

Spanish message board






Newest topics and users posts
20 Oct-01:22:14 Re: art soregaroli's passing (Jim Robison)
19 Oct-22:22:36 Re: art soregaroli's passing (Pete Modreski)
19 Oct-20:49:51 Re: bayley viburnum trend calcite collection (Turbo)
19 Oct-20:44:35 Re: art soregaroli's passing (John S. White)
19 Oct-20:27:35 Re: bayley viburnum trend calcite collection (Bob Harman)
19 Oct-20:22:59 Re: art soregaroli's passing (Robert Seitz)
19 Oct-20:14:59 Re: bayley viburnum trend calcite collection (Turbo)
19 Oct-19:33:21 Art soregaroli's passing (Peter Megaw)
19 Oct-16:42:40 Re: mineralogical museum luigi celleri (mum) of san piero in campo in elba island, italy (Marco Campos-venuti)
19 Oct-16:23:23 Re: scepters - (1) (Marco Campos-venuti)
19 Oct-15:20:48 Re: weird face in quartz (Reef)
19 Oct-13:56:54 Re: collection of michael shaw (Crosstimber)
19 Oct-12:32:29 Re: collection of michael shaw (Tobi)
19 Oct-12:20:55 Re: franjungle collection (Tobi)
19 Oct-12:13:55 Re: alfredopetrovite (Tobi)
19 Oct-11:49:45 Re: collection of manuel mesa (Manuel Mesa)
19 Oct-11:17:09 Re: scepters - (1) (Marco Campos-venuti)
19 Oct-10:26:57 Re: scepters - (1) (Reef)
19 Oct-10:05:30 Re: alfredopetrovite (Alfredo)
19 Oct-07:59:39 Re: alfredopetrovite (John S. White)
19 Oct-07:51:37 Re: scepters - (1) (Marco Campos-venuti)
19 Oct-06:04:24 Re: scepters - (1) (Reef)
19 Oct-01:57:09 Re: alfredopetrovite (Pierre Joubert)
19 Oct-00:36:29 Re: 2015 tucson in retrospect (Robert Seitz)
18 Oct-22:57:24 Re: alfredopetrovite (Alfredo)

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
33969


The time now is Oct 20, 2017 03:59

Search for a textSearch for a text   

A general guide for using the Forum with some rules and tips
2014 - International year of crystallography: for example, pyrite.
  Goto page 1, 2  Next
  Index -> The Ten Thousand Club
Like


View previous topic :: View next topic  
Author Message

Roger Warin




Joined: 23 Jan 2013
Posts: 775


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Dec 26, 2013 04:13    Post subject: 2014 - International year of crystallography: for example, pyrite.  

2014 marks the centennial of the birth of X-ray crystallography, thanks to the work of William Henry, William Lawrence Bragg (father and son) and Max von Laue (the later was awarded the 1914 Nobel Prize in Physics for his discovery of the diffraction of X-rays by crystals).

2014 will be the International Year of crystallography. This is an opportunity to find specific crystalline forms.
The picture shows an euhedral crystal of pyrite from Elba (Rio Marina). This is a typical habit of Elba.
Roger.



Pyrite-Elbe#1_R.jpg
 Description:
Pyrite
Rio Marina - Elba Island - Italy
2 cm
The cubic form is absent in this crystal. The dominant form is pyritohedron (or pentagonal dodecahedron). But some apexes are truncated by secondary forms, such as the octahedron itself slightly truncated by a diploid (or didodecahedron).
A diploid has 24 faces that are formed from the splitting of the pentagonal faces on the 12 sided pyritohedron.
 Viewed:  19984 Time(s)

Pyrite-Elbe#1_R.jpg



Modele-pyrite-Elbe_R.jpg
 Description:
Pyrite
Rio Marina - Elba Island - Italy
drawing
Typical habit of Elba pyrite
 Viewed:  20007 Time(s)

Modele-pyrite-Elbe_R.jpg



Pyrite-Elbe#1-1x_R.jpg
 Description:
Pyrite
Rio Marina - Elba Island - Italy
same specimen
an enlarged apex
{210} pyritohedron
{111} octahedron
{321} diploid
 Viewed:  19996 Time(s)

Pyrite-Elbe#1-1x_R.jpg


Back to top
Reply to topic Reply with quote
Like
   

John S. White
Site Admin



Joined: 04 Sep 2006
Posts: 1192
Location: Stewartstown, Pennsylvania, USA


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Dec 26, 2013 06:15    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

Roger Warin wrote:
Pyrite
same specimen
an enlarged apex
{210} pyritohedron
{111} tetrahedron
{321} diploid

The triangular face is an octahedron, not a tetrahedron.

_________________
John S. White
aka Rondinaire
Back to top
Reply to topic Reply with quote
Like
   

Roger Warin




Joined: 23 Jan 2013
Posts: 775


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Dec 26, 2013 09:23    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

Many thanks John, forgive me. It is a distraction due to age, I guess.
Roger.
Back to top
Reply to topic Reply with quote
Like
   

Jordi Fabre
Overall coordinator of the Forum



Joined: 07 Aug 2006
Posts: 3926
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Dec 26, 2013 09:29    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

John S. White wrote:
The triangular face is an octahedron, not a tetrahedron.

Fixed
Back to top
Reply to topic Reply with quote
Like
   

John S. White
Site Admin



Joined: 04 Sep 2006
Posts: 1192
Location: Stewartstown, Pennsylvania, USA


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Dec 26, 2013 10:00    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

Fixed in only one place, it also needs to be fixed in the first caption.

___________________________________

True. Fixed again... ;-)

Jordi
Back to top
Reply to topic Reply with quote
Like
   

Rodney B Jackson




Joined: 13 Dec 2013
Posts: 12

View user's profile

Send private message

PostPosted: Dec 27, 2013 17:27    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

Naturally formed D&D dice!
Back to top
Reply to topic Reply with quote
Like
   

Riccardo Modanesi




Joined: 07 Nov 2011
Posts: 467
Location: Milano

View user's profile

Send private message

PostPosted: Dec 28, 2013 13:42    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

Hi Roger!
The proper name of the locality is Rio MARINA, not Marino. The specimen is very beautiful, typical of this locality. I found some of these pyrites there.
Greetings from Italy by Riccardo.


Roger Warin wrote:
2014 marks the centennial of the birth of X-ray crystallography, thanks to the work of William Henry, William Lawrence Bragg (father and son) and Max von Laue (the later was awarded the 1914 Nobel Prize in Physics for his discovery of the diffraction of X-rays by crystals).

2014 will be the International Year of crystallography. This is an opportunity to find specific crystalline forms.
The picture shows an euhedral crystal of pyrite from Elba (Rio Marino). This is a typical habit of Elba.
Roger.

_________________
Hi! I'm a collector of minerals since 1973 and a gemmologist. On Summer I always visit mines and quarries all over Europe looking for minerals! Ok, there is time to tell you much much more! Greetings from Italy by Riccardo.
Back to top
Reply to topic Reply with quote
Like
   

Roger Warin




Joined: 23 Jan 2013
Posts: 775


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Dec 28, 2013 15:12    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

Many thanks, Riccardo,
Roger.
Back to top
Reply to topic Reply with quote
Like
   

Jordi Fabre
Overall coordinator of the Forum



Joined: 07 Aug 2006
Posts: 3926
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Jan 06, 2014 13:06    Post subject: Re: 2014 - International year of crystallography  

Roger Warin wrote:
2014 marks the centennial of the birth of X-ray crystallography, thanks to the work of William Henry, William Lawrence Bragg (father and son) and Max von Laue (the later was awarded the 1914 Nobel Prize in Physics for his discovery of the diffraction of X-rays by crystals).

2014 will be the International Year of crystallography. This is an opportunity to find specific crystalline forms....

To know more about the International Year of Crystallography please use the IYCR official web page
Back to top
Reply to topic Reply with quote
Like
   

John Medici




Joined: 02 Mar 2011
Posts: 115
Location: Ohio


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Jan 11, 2014 20:16    Post subject: Re: 2014 - International year of crystallography : for example, pyrite.  

A couple more pyrites to think about.


2006 12 01 016.JPG
 Description:
Pyrite
Barger Quarry, Lexington, VA, USA
2.5 cm on edge
 Viewed:  19069 Time(s)

2006 12 01 016.JPG



2006 12 01 017.JPG
 Description:
Pyrite on quartz
Spruce Claim, King County, WA, USA
3 cm on edge
 Viewed:  19059 Time(s)

2006 12 01 017.JPG



_________________
field collector
Back to top
Reply to topic Reply with quote
Like
   

Rodney B Jackson




Joined: 13 Dec 2013
Posts: 12

View user's profile

Send private message

PostPosted: Feb 05, 2014 17:41    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

Nature is amazing.
Back to top
Reply to topic Reply with quote
Like
   

John Medici




Joined: 02 Mar 2011
Posts: 115
Location: Ohio


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 28, 2014 15:21    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

For those interested, Chemical and Engineering News (C&EN Vol.92,#7 (2/17/2014) )(Newscripts, last page) lists some postage stamps and crystal growing competitions celebrating IYCR.
_________________
field collector
Back to top
Reply to topic Reply with quote
Like
   

Don Lum




Joined: 03 Sep 2012
Posts: 1828
Location: Arkansas


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 28, 2014 17:43    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

John Medici wrote:
For those interested, Chemical and Engineering News (C&EN Vol.92,#7 (2/17/2014) )(Newscripts, last page) lists some postage stamps and crystal growing competitions celebrating IYCR.


Thank you for the information, Dr. Medici.

Don

_________________
hogwild
Back to top
Reply to topic Reply with quote
Like
   

bob kerr




Joined: 13 Nov 2011
Posts: 164
Location: Monroeville PA


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Feb 28, 2014 18:14    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

has anyone noted the very interesting "pyrite after pyrites" from Racracancha Mine, Peru? they appear to be originally cubic pyrite replaced with another crystal form. how would you experts describe this crystal form?

thanks,
bob kerr



pyrite after pyrite.jpg
 Description:
pyrite after cubic pyrite
Racracancha Mine, Tinyahuarco District, Cerro de Pasco Province, Pasco Department, Peru
 Viewed:  18363 Time(s)

pyrite after pyrite.jpg


Back to top
Reply to topic Reply with quote
Like
   

Don Lum




Joined: 03 Sep 2012
Posts: 1828
Location: Arkansas


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Mar 01, 2014 07:56    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

bob kerr wrote:
has anyone noted the very interesting "pyrite after pyrites" from Racracancha Mine, Peru? they appear to be originally cubic pyrite replaced with another crystal form. how would you experts describe this crystal form?

thanks,
bob kerr


Very interesting, Bob. One of the dealers I met in Tucson had some in his room.

Here is his description and I quote:

Pyrite ps. Pyrite
Racracancha Mine, Tinyahuarco Dist., Pasco Prov., Pasco Dept., Peru

A very interesting specimen of pyrite that has pseudomorphed pyrite. I am fairly sure that the numerous small crystals are not epitaxial growths, as fractured surfaces on other pieces show internal voids between the replacement crystals.

Don

_________________
hogwild
Back to top
Reply to topic Reply with quote
Like
   

Martin Rich




Joined: 15 Aug 2013
Posts: 127
Location: Lower Austria


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Mar 01, 2014 20:43    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

Very interesting but I think this is not a "pseudomorph" of Pyrite after Pyrite. Anyway it looks very nice!

Martin

_________________
We are living on the matrix.
Back to top
Reply to topic Reply with quote
Like
   

bob kerr




Joined: 13 Nov 2011
Posts: 164
Location: Monroeville PA


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Mar 02, 2014 09:10    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

possibly not a true pseudomorph - but it seems that the cubic form of pyrite was replaced by another crystal form of pyrite.

so what would this be then? what is the visible pyrite crystal form?

hopefully one of our experts can clear this up.

bob
Back to top
Reply to topic Reply with quote
Like
   

crosstimber
Site Admin



Joined: 30 Apr 2008
Posts: 1137
Location: Oklahoma


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Mar 02, 2014 10:39    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

I have been contemplating this image since I first saw it yesterday, and I had the same impression as Martin. I don't know why you would call this a pseudomorph. The classic definition of a pseudomorph is one mineral replacing another while retaining the crystal form of the mineral being replaced. Perhaps a question of semantics, or maybe not having seen the specimen in person, but to me it looks like the original cubic pyrite crystal has a second generation overgrowth of smaller pyrites with a modified crystal form. I would be very interested to hear Peter Richards weigh in on this one. It's a very nice specimen in any case.

Michael
Back to top
Reply to topic Reply with quote
Like
   

Matt_Zukowski
Site Admin



Joined: 10 Apr 2009
Posts: 576
Location: Alaska


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Mar 02, 2014 17:50    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

Looks to me that etching and recrystallization of smaller crystals on the larger crystal could produce this. If so, not a pseudomorph.
Back to top
Reply to topic Reply with quote
Like
   

Martin Rich




Joined: 15 Aug 2013
Posts: 127
Location: Lower Austria


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Mar 03, 2014 21:15    Post subject: Re: 2014 - International year of crystallography: for example, pyrite.  

Matt, I think you are on the right way. An other possibility is, that a main xl was broken by tectonic forces. A lot of Pyrite crumbles are grown to this smaller crystals as seen on the photograph.

Martin

_________________
We are living on the matrix.
Back to top
Reply to topic Reply with quote
Like
   
Display posts from previous:   
   Index -> The Ten Thousand Club   All times are GMT - 5 Hours
Page 1 of 2
  Goto page 1, 2  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 2006-2017


Powered by FMF