402 GEOLOGY OF THE EUKEKA Dia'iiilGT. 



PLATE VI. 



1. MICROI»EG.MATITIC STliUCTURE IN tlKANlTK-roUrllYltY. 



Thin section Ui. magnifiud 100 diamoters. Intergrowth of quartz and feldspar. The quartz is Iho 

 lighter colored portion in the form of triangles and rhombs. 



2. PI.AGIOCLASK FELDSPAU IN HORXRLENDF.-MirA-ANDKSITr.. 



Thin section 3.5, magnified 32 diameters. Between crossed uicols, exhibiting the parallel growth of 

 twinned individuals and zonal structure. 



