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
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)
20 Mar-14:06:43 Re: dry gill mine, caldbeck fells, cumbria, uk (Forrestblyth)

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
111800


The time now is Mar 28, 2024 07:02

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.
Sensitive minerals
  
  Index -> The Ten Thousand Club
Like


View previous topic :: View next topic  
Author Message

chris
Site Admin



Joined: 12 Jul 2007
Posts: 538
Location: Grenoble


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Oct 24, 2008 12:51    Post subject: Sensitive minerals  

Les presmyk said:
>Tracy, just remember to keep the cinnabar in a box when you are note viewing it and it will remain this color forever.

Hi Les,

I'm very interested by your comment about keeping cinnabar in the box. I thought it was less light sensitive than realgar for instance. Does it mean the color might be altered by long term light exposure ?

If so, do you know what the consequence would be ? As a sulfide collector a nice cinnabar is on my wishing list. But as I prefer to keep my specimens on display (not in a box) I would like to know the consequence(s) of my choice before doing it.

Thanks

Christophe
Back to top
Reply to topic Reply with quote
Like
   

Les Presmyk




Joined: 06 Dec 2007
Posts: 372
Location: Gilbert, AZ

View user's profile

Send private message

PostPosted: Oct 24, 2008 13:19    Post subject: Re: Sensitive minerals  

All cinnabar will darken with exposure to sunlight. It is not the same as realgar where there is a chemical change that takes place. So, keeping cinnabar, like proustite or pyrargyrite, in a box will keep the color red. Actually, I have seen realgars that have been out of the ground and kept in the dark that are as red today as they were 50 years ago when they were collected.
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: Oct 25, 2008 05:03    Post subject: Re: Sensitive minerals  

>All cinnabar will darken with exposure to sunlight.

Right, I don't mentioned it before, assuming that this it is something well know, so it is very useful for me to discover that is not, and that next times I should remember to mention it, not only concerning the Cinnabar but also about all other minerals sensitive to the light or the humidity.

On the other side I'm sorry to disagree with Les. The Realgar is sensitive not only to the light but also to the humidity. Les live in a very dry place, so not doubts about the stability of Realgars well preserved of the light on a so dry places, but in Barcelona, for example, or in other places with high humidity, the Realgars decay, also on the darkness.

Jordi
Back to top
Reply to topic Reply with quote
Like
   

chris
Site Admin



Joined: 12 Jul 2007
Posts: 538
Location: Grenoble


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Oct 25, 2008 13:42    Post subject: Re: Sensitive minerals  

Hello Jordi,

Won't it be useful to create a new thread about this subject ? Sulfides aren't the only minerals which are light sensitive. And it is not always easy to get such information, especially for a beginner.

For instance In France you can find beautiful sky blue fluorite from Haute-Loire... Unfortunately a 30 min direct sunlight exposure turns it colorless ! I know it because I'm French, but how a foreigner would know about it ? And I'm sure you could easily name Spanish examples.

Christophe
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: Oct 25, 2008 14:36    Post subject: Re: Sensitive minerals  

Done Chris. Thanks for your suggestion.

BTW, pink Apatites are also sensitive to the light (them becomes paler). At least the ones from Kazakhstan, Colombia, and less, Pakistan.

Jordi
Back to top
Reply to topic Reply with quote
Like
   

alfredo
Site Admin



Joined: 30 Jan 2008
Posts: 979


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Oct 25, 2008 20:38    Post subject: Re: Sensitive minerals  

A curious fact of no great importance: realgar is only sensitive to green light! So if you filter out the green and only expose it to the rest of the spectrum, its decay will be much less rapid. I don't know whether anyone has ever done this in a display - I suppose you could put it in a glass case illuminted only with a red light bulb.
Back to top
Reply to topic Reply with quote
Like
   

Druid




Joined: 24 Oct 2008
Posts: 9
Location: Cape Town

View user's profile

Send private message

PostPosted: Oct 26, 2008 02:51    Post subject: Re: Sensitive minerals  

Another reason that cinnabar should be kept in a box is due to the fact that it is a mercury based mineral and in hot weather mercury vapors can be released. i have been told to keap mine in a sealed transparent box for viewing purposes.
_________________
Member of the South African Gem and Mineralogical Society
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: Oct 26, 2008 03:17    Post subject: Re: Sensitive minerals  

But this would be suitable only if you have native Mercury on the specimen, because the Cinnabar is highly stable and it don't release mercury at all in hot weather.
The Chinese Cinnabar, for example, have not Mercury on its Dolomite matrix.

Jordi
Back to top
Reply to topic Reply with quote
Like
   

Tracy




Joined: 15 Sep 2006
Posts: 551
Location: Toronto


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Oct 26, 2008 10:20    Post subject: Re: Sensitive minerals  

For there to be any serious risk of being exposed to mercury, I imagine one would have to be surrounded by continuously vapor-releasing specimens in a room with no air circulation (invoking Paracelcus: the dose makes the poison). Surely there is much less mercury in a single cinnabar-mercury specimen than in an old-fashioned thermometer? Even if I am wrong, keeping the windows open in hot weather should give sufficient protection... :-)
_________________
"Wisdom begins in wonder" - Socrates
Back to top
Reply to topic Reply with quote
Like
   

Druid




Joined: 24 Oct 2008
Posts: 9
Location: Cape Town

View user's profile

Send private message

PostPosted: Oct 27, 2008 00:39    Post subject: Re: Sensitive minerals  

Thank you for the correction there folks. that is one of the reasons i am here. to learn :)
_________________
Member of the South African Gem and Mineralogical Society
Back to top
Reply to topic Reply with quote
Like
   

Les Presmyk




Joined: 06 Dec 2007
Posts: 372
Location: Gilbert, AZ

View user's profile

Send private message

PostPosted: Oct 27, 2008 08:41    Post subject: Re: Sensitive minerals  

Jordi, I do not take your comment as disagreement. I was not aware that moisture contributes to the degradation of realgar as well. When one lives in an area that averages less than 19cm of rain a year, we do not deal with humidity related issues. Also, topaz is a mineral that needs to be kept out of direct sunlight, especially those from Utah and Pakistan.

Blue fluorites from Bingham, New Mexico, USA will fade as well. None of this is meant to alarm anyone, just to be cautious. You would have to heat up cinnabar far beyond room temperatures, even in Arizona, to get any off gasing of mercury.
Back to top
Reply to topic Reply with quote
Like
   

alfredo
Site Admin



Joined: 30 Jan 2008
Posts: 979


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Oct 27, 2008 10:12    Post subject: Re: Sensitive minerals  

I agree with you, Les and Tracy. The public tends to assume that if a mineral contains a poisonous element, the mineral must be dangerous. I know a collector who won't buy arsenopyrite crystals because "they contain arsenic, and I have children at home". He doesn't realize his children could hurt themselves more severely by cutting themselves with a broken quartz crystal than anything the arsenopyrite is likely to do to them!

And some of the "not quite so poisonous elements" can actually be WORSE for children, if swallowed. An azurite specimen, swallowed, will be more poisonous than an arsenopyrite, just because it's more soluble in our stomach juices.

Cheers,
Alfredo
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 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