[meteorite-list] A good read on converting standard microscopes to polarizing-chondrule formation

[starsandscopes at aol.com]

Hi list,  Not a typo, one article that  covers such things as conversion of 
a standard bright field microscope to  polarization, various lighting 
techniques, as well as chondrule  formation.

A little slow in parts but then again, this isn't  HBO!

An example to persuade you to take a look or cause you to hit your  delete 
key so fast it's left with fusion crust.

"The "classic" barred  olivine texture is a single plate dendrite 
(Donaldson, 1976) which shares the  entire chondrule with the remaining glass or 
subsequent crystallization  products. Olivine rimming the chondrule is often in 
optical continuity with the  dendrite and thus is part of the plate 
dendrite. Because this texture is so  striking, barred olivine (BO) chondrules are 
well known even to people outside  the field of meteorites. When chondrules 
are discussed, a photomicrograph of a  barred olivine texture is usually 
chosen as one of a few or even the only  example. It is not surprising that 
considerable effort has been expended  understanding its origin. Barred olivine 
textures comprise only a few percent of  melt-textured chondrules, usually 
less than 5% (Gooding and Keil, 1981). The  "classic" barred texture 
represents only 10% of the type 3 ordinary chondrite BO  chondrules. By careful 
study, Weisberg (1987) determined that the multiple plate  dendrite is a much 
more common that the single dendrite. Most investigators  propose that BO 
chondrules form from melt droplets that crystallize rapidly upon  cooling."

Enjoy?  but then check out my Meteorite Micrograph Gallery  hosted by 
Meteorite Times.  I employ most of the techniques outlined in  this article in my 
various image  styles.

http://www.meteorite.com/meteorite-gallery/meteorites-alpha_frame.htm

Tom  Phillips