January 24 Through February 4—TUCSON, ARIZONA: Annual show
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Thu Mar 28, 2024 4:11 pm

All times are UTC - 4 hours




Post new topic Reply to topic  [ 7 posts ] 
Author Message
 Post subject: Blue Chalcedony rough?
PostPosted: Sun Mar 11, 2012 12:39 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 12, 2008 3:00 pm
Posts: 177
Location: Wisconsin
I found this in a flat that I purchased at an estate sale a few year ago, no info ](*,) :smt013 . I have always wondered if it was Chalcedony? :-k and if there are ways I could test it and see :-k . Any and all help is greatly appreciated :-D


Attachments:
PICT3189.JPG
PICT3189.JPG [ 60.46 KiB | Viewed 1760 times ]
PICT3188.JPG
PICT3188.JPG [ 65.72 KiB | Viewed 1760 times ]
PICT3186.JPG
PICT3186.JPG [ 74.93 KiB | Viewed 1760 times ]

_________________
Troy Nelson
Top
 Profile  
Reply with quote  
 Post subject: Re: Blue Chalcedony rough?
PostPosted: Sun Mar 11, 2012 4:58 pm 
Offline
Established Member

Joined: Sat Feb 16, 2008 8:11 pm
Posts: 43
Location: Portland, Oregon
The margins appear to be. However, it looks more grayish and with an intergrowth of quartz crystals in the center.


Top
 Profile  
Reply with quote  
 Post subject: Re: Blue Chalcedony rough?
PostPosted: Sun Mar 11, 2012 5:12 pm 
Offline
Site Admin
User avatar

Joined: Fri Apr 17, 2009 3:53 pm
Posts: 2049
Location: Sweden
Probably chalcedony but not likely to be really blue.

_________________
_____________
Conny Forsberg


Top
 Profile  
Reply with quote  
 Post subject: Re: Blue Chalcedony rough?
PostPosted: Sun Mar 11, 2012 5:18 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 12, 2008 3:00 pm
Posts: 177
Location: Wisconsin
Thank you Emprean Gems! Yes it does have quarts in the center, the color does appear blue with a grayish hue. Is this piece worth while for cutting or should it be just keep as a mineral speciment?

_________________
Troy Nelson


Top
 Profile  
Reply with quote  
 Post subject: Re: Blue Chalcedony rough?
PostPosted: Sun Mar 11, 2012 5:23 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 12, 2008 3:00 pm
Posts: 177
Location: Wisconsin
I will try to post a new photo with a white background, I am wondering if the red background is throwing off the color a little bit?

_________________
Troy Nelson


Top
 Profile  
Reply with quote  
 Post subject: Re: Blue Chalcedony rough?
PostPosted: Sun Mar 11, 2012 5:52 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Mar 12, 2008 3:00 pm
Posts: 177
Location: Wisconsin
We have a bright sunny day, so I took it outside for a closer look in the sunlight. It appears to be clear (color not transparentcy) with many layers stacked on top of one another showing a blue coloration. I guess I will label this one clear or gray.

_________________
Troy Nelson


Top
 Profile  
Reply with quote  
 Post subject: Re: Blue Chalcedony rough?
PostPosted: Tue Mar 13, 2012 4:15 pm 
Offline
Gold Member

Joined: Sun Jun 28, 2009 9:56 am
Posts: 1284
I think this could well be massive quartz

'massive' means it's not crystallised, still quartz is a material of crystalline structure, but it is not always expressed as crystals (massive doesn't mean amorphous or cryptocrystalline structure).

Massive quartz with a greyish color with slight bluish hue isn't unusual

here's a pic I took inside an iron mine which shows such grayish quartz: http://img524.imageshack.us/img524/4796/insitumf6.jpg

quartz (would it be in crystallised or massive form) will show anisotropic reaction under polariscope (during 360° rotation stone blinks 4 times, light and dark), while amorphous silica (opal) would remain dark, and cryptocrystalline silica (chalcedony) would remain lit.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 7 posts ] 

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 8 guests


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 post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Gemology Style ported to phpBB3 by Christian Bullock