ee By OVE: 
MICROSCOPIC STRUCTURE OF MINERALS AND ROCKS. 
Ihe 
2. 
3. 
4 

Crystallites and Microlites in glassy base. Pitchstone. 
Lath-shaped crystals of Felspar m glassy base. Andesite. 
Spherulites in clear glass. Obsidian. 
Perlitic structure. Pitchstone. 
bo 
Or 
. 
[Between pages 24 and 
