PHYSIOGRAPHY. 159 



Cube-Ore Cummingtonite Cupreous Anglesite. 



3. Cube-Ore is chiefly found in veins of copper ores in the older class- 

 i of rocks, where it is accompanied by Vitreous Copper, Fahlerz, Whit* 



Iron-Pyrites and Quartz. 



4. It is principally found in Cornwall, in several copper-mines, in the 

 neighborhood of Red ruth, but has also been found at St. Leonhard in 

 France, and at Schwarzenberg in Saxony. 



In the United States, it has been met with in drusy coatings, along 

 with Mispickel, Iron, and Copper Pyrites, at Edenville in Orange coun- 

 ty, (N. Y.) where these minerals exist in gneiss ; and under similar cir- 

 cumstances in Derby, (Conn.) 



CUMMINGTONITE. Hemi-prismatic Wavel- 

 line-Spar? 



Massive : composition thin columnar, scopiform and stel- 

 lular, rather incoherent; fibres somewhat curved. 



Cleavage parallel to an oblique rhombic prism. 



Lustre silky, color ash-grey. Translucent to opake. 



Brittle. Hardness =6-,5. Sp. gr. =3-2014. 



1. Alone before the blow-pipe, it is infusible, except on very thin 

 edges. With carbonate of soda it fuses with effervescnce into a dark 

 glass. With borax it fuses into a black glass. 

 2. Analysis. 

 By MUIR. 



Silica .... 56-543 



Protoxide of iron - - - 21.669 

 Protoxide of manganese - - 7-802 



Soda 8-439 



Volatile matter .... 3-178 



8. Cummingtonite is found at Plainfield and Cummington, (Mass.) 

 in mica-slate, associated with Garnet and White Iron- Pyrites. 



CUPREOUS ANGLESITE. Cupreous Lead- 



Bary te. 



Primary form. Right oblique-angled prism. M on T 

 =102 45'. 



