594 THE GEOLOGY OF MINNESOTA. 



[Jaspilyte. Hematite. 



The sample was collected to show a blending of the green schists and the jaspilyte, 

 but this sample seems to contain but little more quartz than the ordinary green schist. 

 Mic. A schistose rock composed of quartz, perhaps also feldspar, chlorite, mus- 

 covite and iron ore. Similar to No. 896. One section. 



Age. Keewatin. u. s. o. 



No. 899. JASPILYTE. 



Near Tower. 



Ref. Annual Report, xv, pages 232, 388; Bulletin ii, pages 234, 421. 



Meg. A white jaspilyte with spots and blotches of reddish. A little weathered 

 pyrite is present. 



Mic. The section is made up essentially of the fine-grained quartz common to 

 the jaspilytes, but in this case the grains are some larger than is customary. 

 Scattered through the slide are small grains of iron ore, some of which are octahe- 

 drons, probably of magnetite. There are also irregular areas which show a brownish 

 stain. One section. 



Age. Keewatin. u. s. G. 



No. 900. JASPILYTE (with magnetite crystals). 



Near Tower. 



Ref. Annual Report, xv, pages 232, 388; Bulletin vi, pages 234, 421. 



Meg. Gray to black, banded jaspilyte. The black is due to magnetite, and 

 small, glistening crystals (usually octahedrons) of this mineral are scattered through 

 the sample. 



Mic. The section is composed of fine-grained quartz and crystals of magnetite. 



One section. 



Age. Keewatin. u. s. G. 



No. 901. HEMATITE. (Earthy.) 



Lee mine, Tower. 



Ref. Annual Report, xv, page 388. 



Meg. Soft, impure, dark-red, earthy hematite. The field notes designate this 

 as " ' baked clay,' near contact with the jaspilyte." 

 No section. Compare No. 904. 



Age. Keewatin. u. s. G. 



No. 902. JASPILYTE (with vein/ets). 



Stone mine, Soudan. 



Ref. Annual Report, xv, page 388. 



Meg. Banded jaspilyte, composed of broad, deep red bands, and narrow black 

 ones. The red bands are of hematite and quartz, and the black ones of hematite, 

 quartz and crystals of magnetite. The hand specimen shows nicely the folding of 

 the rock. 



