Professor Emerson on IlalVs Geological Collections. 559 



29. Granite. 



A pale reddish rock very fresh in the interior but much weathered on the 

 exterior, containing a fresh transhicent plagioclase in large quantity, limpid 

 slightly amethystine quartz, and sparingly black shining biotite. 



Locality, Frobisher Bay. 



30. Gkanite. 



A coarse-grained granite, containing flesh-red orthoclase and gray plagio- 

 clase in large masses, dark smoky quartz and black mica in small quantity. 



From a package labeled " From various places up Bay of Frobisher and near 

 head of it." 



31. Granite. 



A peculiar very coarse-grained leek-green rock, consisting principally of 

 grayish to deep leek-green plagioclase, in large cleavable individuals, showing 

 very fine triclinic striation, gray translucent quartz, very little flesh-colored ortho- 

 clase, and large contorted plates of black shiny lepidomelane. 



Frobisher Bay. 



32. Granite. 



A deep-red rock, fine-grained, with abundant fresh plagioclase, orthoclase, 

 black biotite, and large red garnets. 

 Frobisher Bay. 



33. Pyritiferous &ranite. 



A coarse-grained very quartzose granite, with much pyrite in large, quite 

 distinct, crystals. Biotite and feldsi>ar occur very sparingly. The quartz is 

 smoky to slightly amethystine. By the decomposition of the pyrite the rock has 

 upon the surface and in the fissures a very rusty and glazed appearance; the feld- 

 spar is changed entirely to whitish kaolin and the biotite to rubellan. 



Locality, French Head, Field Bay. 



34. Granite. 



A black mica granite passing into quartzite. 



35. Granite. 



A beautiful fine-grained granite of dark color, containing abundantly red 

 brown biotite unusually fresh and shining, gray quartz, from which the feldspar 

 is with difficulty distinguished. 

 30. Granite. 



A very granular even-grained rock, containing orthoclase, quartz, and bio- 

 tite in about equal quantity. 



Labeled, " Azoic Rocks, Frobisher Bay." 



