PETROGRAPHIC GEOLOGY AKD DESCRIPTIONS. 795 



Basalt. Quartz-porphyry. Quartzyte.] 



No. 1834A. BASALT. 



Same place as No. 1834. 



Ref. Annual Report, xxii, page 8. 



Meg. A collection of the spherical masses from No. 1834. See under No. 544. 

 No section. 



Age. Manitou. u. s. G. 



No. 1834C. QUARTZ-PORPHYRY. 



From a hill rising about 600 feet above lake Superior, about a mile and a half from Grand Portage village 

 and on the west of the Grand Portage trail. Perhaps in sec. 31, T. 64-6 E. 

 Ref. Annual Report, xxii, page 9. 



Meg. Red, fine-grained, granitic rock, with phenocrysts of quartz and red 



feldspar. The specimen resembles closely the porphyritic phase of the " red rocks " 

 found on Pigeon point. No section. 



Age. Cabotian. u. s. G. 



No. 1838. QUARTZYTE. ( Metamorphic. ) 



Foot of mount Josephine, head of Wauswaugoning bay. 

 Ref. Annual Report, xxii, page 9. 



Meg. Upper portion of the Wauswaugoning quartzyte, gray, finegrained, some- 

 what colored like the slates, spotted with light red, pink, or even green, depending 

 on the character of the incipient re-crystallization. 



Mic. Consists very largely of quartz, which has lost its clastic characters under 

 the influence of the basic intrusives of the place, only showing the original outlines 

 of the grains by curving bands of opaque inclusions. The red material is feldspar, 

 as shown by an occasional interference figure of a biaxial character. This material 

 composes perhaps one-fifth part of the whole, while hornblende, pennine and epidote 

 are occasional, the first most common. Two sections. 



Age. Animikie. N. H. w. 



No. 1839. QUARTZ-PORPHYRY. 



Same place as Nos. 1837 and 1838, appearing in patches in No. 1838. 

 Ref. Annual Report, xxii, page 9. 



Mcy. Very fine-grained, reddish rock, with phenocrysts of quartz and pinkish 

 feldspar. No section. 



Age. Cabotian. u. s. G. 



No. 1841A. QUARTZYTE. (Spotted.) 



From the beach near the head of Morrison bay, Pigeon point ; N. E. % sec. 32, T. 64-7 E. 

 Ref. Annual Report, xxii, page 9. 



Meg. There are several specimens, varying somewhat, but in general they are 

 fine-grained, hard, gray quartzytes, with spherical areas, one-fourth to one-half inch 



