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 10:38 am

All times are UTC - 4 hours




Post new topic Reply to topic  [ 14 posts ] 
Author Message
 Post subject: Identification
PostPosted: Thu Feb 16, 2012 12:07 pm 
Offline
New to the Forum or The Quiet Type

Joined: Thu Feb 16, 2012 9:39 am
Posts: 1
Have recently started thoughts of gem collecting, and wonder if you are able to ID a piece.

It consists of around 40 beads, very clear (at least to the eye anyway) with around 15 sides (???facets???) on each bead. It is colourless, however when moved around in, the light passing through it gives off different colours on each side, they are typically red, orange/yellow, green and possibly blue (if I can remember rightly). Each bead is around 10mm in diameter and the overall weight must be c. 200grams. I do not think it is pleochroic (as these gems tend to favour a certain colour and then 1 or 2 other colours can be seen within, whereas these are purely colourless, but the light passing through gives out many colours on each side). I have been unable to distinguish it using the internet, so any ideas greatly welcome,

Ben


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 6:21 am 
Offline
Valued Contributor

Joined: Wed Sep 15, 2010 4:12 am
Posts: 114
Location: Belgium
my guess : coated glass (like this : http://image.made-in-china.com/2f0j00yC ... -S093-.jpg )

_________________
Marc
http://www.gemsdat.be/engels.htm


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 7:07 am 
Offline
Site Admin
User avatar

Joined: Fri May 12, 2006 11:24 am
Posts: 7523
Location: Rome, Italy
hi and welcome to the forum

sailorben wrote:
Have recently started thoughts of gem collecting, and wonder if you are able to ID a piece.


i would warn you nothing can be positively identified by seeing a picture...... you would have a clue by providing written infos only?
if you'r not able to give us at least some more infos (RI, SG et als) guess we 're loosing time here, sorry..... :roll:

ciao
alberto

_________________
GemmoRaman-532 - GemmoFTIR - GemmoSphere - EXA


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 10:55 am 
Offline
Active Member

Joined: Sat May 21, 2011 7:09 am
Posts: 77
Location: Italy
Hi Sailorben,
colorless gemstone can not be pleocroic! [-X

Wait for a night with a clear visible moon, and check if your stones are birefringent (by using the visual opitcs method).


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 11:03 am 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 21602
Location: San Francisco
In order to ID something you have to test it, even in the most rudimentary way.
If you have no tools, you can start with a laptop screen and a pair of polarized sun glasses.
If you suspect glass, touch it to your forehead. Warm or cold?
Magnification may reveal fracture surfaces or inclusion which can he helpful.

Many things have been previously discussed on the board.
Search about a bit. :D

Sidebar, where exactly CAN one learn the visual optics method.
There are some sites online which describe it, but someone needs to make a really good tutorial with some videos and post it. hint hint


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 12:39 pm 
Offline
Site Admin
User avatar

Joined: Fri Apr 17, 2009 3:53 pm
Posts: 2049
Location: Sweden
I guess pleochroic in the above post actually means dispersion...

_________________
_____________
Conny Forsberg


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 1:46 pm 
Offline
Gemology Online Royal Princess

Joined: Mon Oct 17, 2005 10:56 am
Posts: 6461
Location: The frozen north prairie :-/
Barbra ... No video, but here's where I printed out the instructions (although I still haven't quite got the hang of it #-o ).

_________________
IIJA Registered Gemologist
GIA Graduate Gemologist


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 2:44 pm 
Offline
Gold Member

Joined: Mon May 14, 2007 11:00 am
Posts: 1133
Location: Monterey, CA
Barbara,
Perhaps if you also included consideration of the B:D ratio you might derive more useful information.


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 3:03 pm 
Offline
Gemology Online Royal Princess

Joined: Mon Oct 17, 2005 10:56 am
Posts: 6461
Location: The frozen north prairie :-/
Dr. Bill,

If I actually sat down and practiced, I'd probably get the hang of it! :oops: 8)

_________________
IIJA Registered Gemologist
GIA Graduate Gemologist


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Fri Feb 17, 2012 10:42 pm 
Offline
Platinum Member

Joined: Tue Nov 29, 2005 2:02 pm
Posts: 2646
Conny Forsberg wrote:
I guess pleochroic in the above post actually means dispersion...

I'm thinking iridescence, but who knows...


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Sat Feb 18, 2012 12:54 am 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 21602
Location: San Francisco
Bill Hanneman wrote:
Barbara,
Perhaps if you also included consideration of the B:D ratio you might derive more useful information.

Fair enough.
Start from the beginning, Dr. Hanneman and post a thorough tutorial.
The ball is now in YOUR court.
:D


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Sat Feb 18, 2012 5:43 pm 
Offline
Gold Member

Joined: Mon May 14, 2007 11:00 am
Posts: 1133
Location: Monterey, CA
Barbra Voltaire wrote:
Bill Hanneman wrote:
Barbara,
Perhaps if you also included consideration of the B:D ratio you might derive more useful information.

Fair enough.
Start from the beginning, Dr. Hanneman and post a thorough tutorial.
The ball is now in YOUR court. :D

Indeed it is, and you merit a response. But first, let us look at this from my perspective.

As you well know, I have written and sell a book (Guide to Affordable Gemology, $40) in which a full nine pages are devoted to this particular topic. Also, along with my filters, I market a set of plastic cards (Model 2004 - 10 sides, $20) which explains how to practice this technique. Therefore, your request for me to post on your site a "thorough tutorial" on this subject does not initially strike me as something a prudent business man would do.

On the other hand, through your forum, I do believe you are performing a very useful service to the field and future of gemology, and you deserve as much encouragement as it is possible to give. Therefore, let me propose the following. I will grant you permission to reproduce the copywrited pages 144-152 from my book as a "tutorial". You, however, will have to translate it into a PDF or whatever to fit your own format.

I trust this puts the ball back in your court. :D :D


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Sun Feb 19, 2012 11:08 am 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 21602
Location: San Francisco
I can do that......certainly.
I'll format that later today and give it a permanent home for everyone's reference.
Excellent.
:D


Top
 Profile  
Reply with quote  
 Post subject: Re: Identification
PostPosted: Sun Feb 19, 2012 2:22 pm 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 21602
Location: San Francisco
The pdf of the excerpt from Dr. Hanneman's Guide to Affordable Gemology is available here:
Gemstone Recognition Without Instruments:
http://gemologyonline.com/hanneman.pdf
and in addition an HTML page has been added to our site, listed on the left entitled:

Gemstone Recognition Without Instruments, by W.Wm Hanneman

In addition:
http://www.gemstoneartist.com/GemID.asp


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 14 posts ] 

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 12 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