Caix" Fiiulivind, Bulh.r Co. — A coarse grained, jjfrey rock, with 

 biotite rather abundant. Sometimes with porphyritic crystals of 

 orthoclase up to two inches in length but allotriomorpliic. S.(t. 

 2-Gl to -l-Q-l. Section : Quartz, orthochxso, phigioclase, l)iotite, 

 and nuiscovite. The quartz is cliiefly granulicic, the grains about 



mucli of it is reduced to grains -00?) in diameter ; it surr-ounrls 

 tlic telspars and biotites. Tlie orthoclase is generally allotrio- 

 inorphic ; phigioclase in subordinate quantity only, the biotite 

 IS uniaxial ; the muscovite in small quantity. Plagioclase, nuis- 

 covite, zircon, and apatite occur as inclusions in the orthocla..e. 



The porpliyiitic orthoclases are elongated in the direction of the 

 ortho-diagonal. Thoy consist of narrow alternating layers of 

 orthoclase and microcline paralhd to the elino-pinac-oid^ with 

 irregular bands of another felspar (probably albite) roughly 

 parallel to the ortho-pinacoifl. The polarization colours are lo'west 



meats of much altered clastic rocks, some of which are surrounded 

 15. -Without Muscovite. (Granitite.) 



,l;i .1 uu Uuun. Orthoclase up to "13 ; plagioclase is (^uite suboi-dinate. 

 C r(i.-,.-hatrhing of microcline is plainly seen on some of tin; felspars, 

 wluie others have a coarser structure like polvsyntlictic twinning 

 on botli Hlbit(> and pericline types. Sphene" occurs occasionally 

 and a litth; clilorite after biotite. 



Lab' 1\„ ,-./„, W, s//,,„./-.x rather line grained, grey, rock with 



■.K!„„-|,tv'and' 



l.iotite. 



The < 



lU'irtzo 



. are rarely 



.;■■;;,:::::::{;:;: 



hmg of , 



nulati. 



zr 



- di.tin.-tly. 

 There is no 



It.' i. al.undam 



t, from 



'•03 'to 



•Oi ii 



I diameter. 



'!i'''v.'/-AH, 



10 grained rock 



, with ; 



^rey felspar 





of l.ioti 





G. 2-7( 





■ plagioclase, ar: 



a\ biotit< 



'.The 



.juart/. 



-^arela^f% 



•01.>, and shew 









ion. They 



- and liquid-cavi 



ties hi' b 



'andbf 



''Theo 





