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
04 Jun-20:17:45 Re: don lum collection (Don Lum)
04 Jun-15:27:00 Re: the mizunaka collection - stibnite (Am Mizunaka)
04 Jun-08:39:41 Re: collection of michael shaw - malachite (Michael Shaw)
04 Jun-01:49:14 Re: the mizunaka collection (Jordi Fabre)
03 Jun-21:44:21 The mizunaka collection - stibnite (Am Mizunaka)
03 Jun-06:16:31 Re: collection of volkmar stingl (Volkmar Stingl)
02 Jun-13:39:20 Re: don lum collection (Don Lum)
02 Jun-08:51:39 Re: collection of michael shaw (Michael Shaw)
02 Jun-02:27:53 The mizunaka collection - rhodchrosite (Am Mizunaka)
02 Jun-01:36:07 Re: collection of volkmar stingl (Volkmar Stingl)
02 Jun-01:17:41 Re: is this a rhyolite matrix with calcite and smoky quartz? (Volkmar Stingl)
01 Jun-22:11:04 Re: is this a rhyolite matrix with calcite and smoky quartz? (Roger Warin)
01 Jun-20:02:10 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Alfredo)
01 Jun-10:24:08 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Rick Roan)
01 Jun-10:21:30 Is malachite rare? (Matt_zukowski)
01 Jun-09:51:59 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Matt_zukowski)
01 Jun-09:21:32 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Rick Roan)
01 Jun-07:40:50 Re: mineral identification tips (Cascaillou)
31 May-16:04:59 Is this a rhyolite matrix with calcite and smoky quartz? (Gk68)
31 May-15:40:58 Re: don lum collection (Don Lum)
31 May-15:40:12 Re: is this dolomite-pyrite-siderite? (Gk68)
31 May-09:28:53 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Rick Roan)
31 May-08:49:08 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Alfredo)
31 May-07:33:18 Re: is it possible for this specimen of hyalite to be associated with other minerals? (Rick Roan)
31 May-07:26:07 Re: is it possible for this specimen of hyalite to be associated with other minerals? (James Catmur)

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
113265


The time now is Jun 05, 2024 02:10

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.
Quartz twinning -- brazil law, or contact area fluke
  
  Index -> Minerals and Mineralogy
Like


View previous topic :: View next topic  
Author Message

Scott LaBorde




Joined: 14 Dec 2009
Posts: 104
Location: North Carolina


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Nov 09, 2010 09:46    Post subject: Quartz twinning -- brazil law, or contact area fluke  

I recently found this quartz crystal in the dump piles of old quartz mine in NC. There is an unusual area on the crystal that seems to signify x or s faces oriented in such a way as to represent a brazil law. However, the faces are atypical of a textbook morphological brazil law twin. It was suggested this may be a contact area between this crystal and another and the striations are simply the by-product so to speak. I have seen this "stair step pattern" myself as a result of a juxtaposed crystals so it does seem plausible. Any thoughts or suggestions?


randolph.JPG
 Description:
Notice the s and x face visible on the left indicating a left handed crystal. The striations on the right side have me baffled. If they were s faces with the striations it would seem to suggest it's both left and right, but then what face is in the middle?
 Viewed:  7273 Time(s)

randolph.JPG



brazil_law.JPG
 Description:
The crystal. Not entirely in focus because I just wanted to show the faces in question.
 Viewed:  7291 Time(s)

brazil_law.JPG



_________________
Scott LaBorde
Back to top
Reply to topic Reply with quote
Like
   

Pete Richards
Site Admin



Joined: 29 Dec 2008
Posts: 830
Location: Northeast Ohio


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Nov 19, 2010 13:11    Post subject: Re: Quartz twinning -- brazil law, or contact area fluke  

I think it's a scar from contact with another crystal. Sorry, Scott.

Pete Richards

_________________
Collecting and studying crystals with interesting habits, twinning, and epitaxy
Back to top
Reply to topic Reply with quote
Like
   

Scott LaBorde




Joined: 14 Dec 2009
Posts: 104
Location: North Carolina


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Nov 19, 2010 16:24    Post subject: Re: Quartz twinning -- brazil law, or contact area fluke  

Yes, I have capitulated to a contact feature origination. It's the only thing that would explain it. Thanks for looking :).
_________________
Scott LaBorde
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 2006-2024


Powered by FMF