Dec.20 to 22:SAN DIEGO, CALIFORNIA: Wholesale and retail show; Gem Faire Inc.; Scottish Rite Center; Fri. 12-6, Sat. 10-6, Sun. 10-5;
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Mon Dec 09, 2019 12:49 am

All times are UTC - 4 hours




Post new topic Reply to topic  [ 2 posts ] 
Author Message
 Post subject: Biaxial - 3 Refractive Indices - Trichroic...........
PostPosted: Sat Jan 17, 2015 12:27 pm 
Offline
Established Member

Joined: Fri Mar 21, 2014 9:10 pm
Posts: 30
I am a bit confused about something..........

CUBIC System is ISOTROPIC with 1 Refractive index

TRIGONAL
TETRAGONAL
HEXAGONAL are all ANISOTROPIC with 2 Refractive indices

ORTHOHOMBIC
MONOCLINIC
TRICLINIC are all ANISOTROPIC with 3 Refractive indices

On the refractometer:

Cubic & amorphous gems show 1 shadow edge
Trigonal, Tetragonal & Hexagonal gems show 2 shadow edges

In the case of Ortohombic, Monoclinic & Triclinic gems are we able to see all 3 refractive indices?

Can we see them only if the stone is turned?
Can we see three shadow edges at all?


Top
 Profile  
Reply with quote  
 Post subject: Re: Biaxial - 3 Refractive Indices - Trichroic...........
PostPosted: Sat Jan 17, 2015 1:35 pm 
Offline
Site Admin
User avatar

Joined: Sun Oct 16, 2005 12:22 pm
Posts: 19943
Location: San Francisco
I moved your post to a more appropriate place.
Perhaps reading through this Gemology Project article might be useful.
http://www.gemologyproject.com/wiki/ind ... ractometer


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 1 guest


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