422 



MINERALOGY 



FIG. 469. Enstatite. Bamle, Norway. 



developed at an angle near 88. Pleochroism varies with the iron 

 content ; it is almost absent in enstatite and well marked in hyper- 

 sthene, changing from brown to green when parallel to the axis 6. 

 Interference color," upper first order. The acute bisectrix in ensta- 

 tite is parallel to c, and when iron reaches 10 per cent, it changes 

 to the axis &. 



Inclusions are very characteristic, consisting of microscopic crys- 



FIG. 470. Section of Enstatite showing the Regularly Arranged Inclusions 

 causing the " Schiller." 



tals in plates, rods, or grains, arranged parallel to the brachy- 

 pinacoid, producing the " schiller " so characteristic of these two 



