Vol. 4] Murgoci. — Classification of the Amphiboles. 



393 



recall those of tourmaline. Max. ext. — 12°, y — a = 0.002, 2 V 

 small, axial plane transversal to cleavage. 



Glaucophane and iitanite. San Pablo (studied and analysed 

 by Blasdale, loc. cit.). No. 126. See my determinations on uni- 

 axial glaucophane in the first part of this paper. 



Glaucophane schist. North Berkeley. 



Glaucophane, ext. -5^; on cleavage lamellae -7°; 2 V small ; 

 negative; y — a and y — (3 as usual. 



Gla ucophane (boulder). San Pablo. No. 123. Analysed by 

 Blasdale. The colors of the pleochroism not intense; ext. mi 

 cleavage lamellae, -10° (8°-10°), 2 V small. 



Eclogite with glaucophane. Russian River. No. 2114. 



Glaucophane qtiartzite. Wildcat Creek. North of Berkeley. 



Garnet; titanite; glaucophane in pale colors, ext. -4°-6° on 

 cleavage lamellae (one lamella gave -14°) ; the prisms have the 

 orthopinacoidal faces more developed than the clinopinacoidal 

 ones; 2 V very large. 



Mica seliist. North Berkeley. 



Pale glaucophane, ext. on cleavage lamellae, -8° ; 2 V large. 

 Chlorite. 



Quartzite. North of Berkeley. 



Crossite quite identical with that of Palache. Very intensely 

 colored; absorption and dispersion very large; max. ext. -20°; 

 /? — a > y — f3 ; axial plane transverse to the prism ; C = opacpie 

 violet, f) = Prussian blue; a = yellowish green. 



SYENITES, ETC. 



Syenite. Spanish Peak, Plumas County, California. 

 Apatite as needles and bunches ; rutile as formless grains, often 

 as pseudomorphoses of fragments of amphibole ; leucoxene as 

 halo around some rutiles, or as patches ; ferruginous patches ; 

 chlorite and biotite with weak pleochroism, very small angle of 

 the optic axes ; negative. Albite, katophorite. Secondary quartz 

 and crocidolite. 



The katophorite is smoky yellow, without appreciable 

 pleochroism; C>6>3. The color seems to be due to a 

 pigment which is not evenly distributed through the whole min- 

 eral ; at all events, the periphery is lighter in color and clearer 



