754 THE GEOLOGY OF MINNESOTA. 



[Conglomerate. Granite. Grit. Quartzyte. 



Remark. The green element in this rock is evidently derived from a debris 

 from the Archean greenstones. It never shows the taconitic globular structure. 

 That appears at a higher horizon and at this place contains only quartz and iron ore. 



N. H. w. 



No. 1635. CONGLOMERATE. 



The lower portion of No. 8 of the drill at Wicks'. 



Ref. Annual Report, xxi, pages 83, 153 ; Annual Report, xxii, page 160. 



Meg. No. 8 consists of " greenstone " materials embracing many pebbles and 

 grains of quartz. 



Nic. The slide is made from the lower portion of No. 8 and consists of a 

 granitic debris with considerable infiltration and alteration. This debris is old 

 feldspars now containing much muscovite, some being apparently oligodase and some 

 orthoclase, quartz, hornblende (largely chloritized), leucoxene (alteration from sphene) 

 and chlorite. One section. 



Age. Animikie (Pokegama). N. H. w. 



No. 1636. GRANITE. 



No. 10 of the drill at Wicks'. 



Ref. Annual Report, xxi, pages 83, 153 ; Annual Report, xxii, page 160. 



Meg. Granite. 



Mir. The rock is not fresh, but consists of coarse oligodase,, microcline, orthoclase 

 and quartz, of which quartz is the latest, with small amounts of pennine, apatite, 

 calcite and sphene, and with much kaolinic alteration throughout the feldspars. 

 One section. 



Age. Archean (granite). N. H. w. 



No. 1637. GRIT. (Green.) 



N. E. % S. W. % sec. 22, T. 60-13, near Wicks', on the Mesabi range. 

 Ref. Annual Report, xxi, pages 83, 84, 153. 



Meg. Like No. 1634, mainly fragraental material (green), in which are con- 

 spicuous grains of lavender quartz. 



Mic. The green color of the rock is due to debris of green hornblende largely 

 chloritized, but in which are distributed coarse quartzes, with irregular borders and 

 large irregular crystals of microcline. One section. 



Age. Animikie (Pokegama). N. H. w. 



No. 1638. QUARTZYTE. 



S. E. y N. W. % sec. 28, T. 60-13, near Wicks', on the Mesabi range. 

 Ref. Annual Report, xxi, pages 84, 153. 



Meg. Nearly all quartz, in form of clastic grains. 



