penny just dropped - Reflected Light Petrography

Paul bristolia at yahoo.com
Sat May 17 20:32:21 EDT 2008

Dave Harris wrote:


>I am sure I saw some reference on the list about

>these Nantan thin sections that appear on Fleabay.

>Having just got a polarizing scope I just realised

>that they can either be ruut t/s or completely

>opaque as Fe and sulphides are opaque to the

>standard 30 micron thickness, and would be a

>bit dull anyway - expecially looking at rust!

>How funny - shows I learnt SOMETHING already

>about mineral optics


There are petrographic microscopes, which use reflected polarized light to
conduct petrographic analysis of opaque minerals in polished thin sections.
To take advantage of reflected light petrography, the thin sections usually
have to be polished.

Determination of opaque minerals in reflected light microscopy
http://www.unige.ch/sciences/terre/mineral/fontbote/opaques/opaques_properties.html

Ore Petrology and Phase Equilibria
http://www.agu.org/revgeophys/mckibb01/node11.html

Ore (Petrographic) Microscopes
http://www.oremicroscopes.com/

Trinocular Ore Polarizing Petrographic Microscope
http://usbmicroscopes.biz/usb-microscope/trinocular-ore-polarizing-petrographic-microscope/

A couple of books:

Ore Microscopy and Ore Petrography by James R. Craig and David J.
Vaughan (1994), ISBN:0471551759

Atlas of the Textural Patterns of Ore Minerals and Metallogenic
Processes by S. S. Augustithis (1995) ISBN:3110136392

Bunch, T. E. and A. M. Reid, 1975, The Nakhlites. I - Petrography and mineral
chemistry. Meteoritics. vol. 10, pp. 303-315, pp. 317-324.

Yours,

Paul H.