208 PHYSIOGRAPHY. 



Staurotide. 



with crystals of Kyanite, into a continuous mass with parallel axes, the 

 perfect planes of cleavage of the two crystals being coincident. Twin- 

 crystals occur in Spain, Portugal, France, Scotland and Brazil. 



It is particularly abundant in the mica-slate region of the United 

 States. The most interesting localities for the size and perfection of its 

 crystals are, Franconia, (N. H.) New York, three and a half miles 

 from the city, Bolton and Tolland, (Conn.) Chesterfield, (Mass.) Harps- 

 well and Winthrop, (Maine.) 



STEATITE. See Talc.) 

 STEINHEIJLITE. (See lolite.) 



STERNBERGITE. Monotomous Polypoione- 

 G Ian c e. 



Primary form. Right rhombic prism. M on M =119 

 30'. 



Secondary form. Primary form, with the acute edges 

 truncated. 



Cleavage, highly perfect parallel to P ; the lamina? may 

 be torn asunder like thin sheet-lead. 



Lustre metallic. Color dark pinch-beck brown. Streak 

 black. Tarnish often violet-blue. 



Very sectile. Thin laminae perfectly flexible. Hard- 

 ness = 1-0 . . . 1-5. Sp. gr. =4-215. 



Compound Varieties. Globular, or rose-like aggrega- 

 tions. Massive : composition granular. 



1. Alone on charcoal, it burns with a blue flame and sulphurous odor, 

 and melts into a globule generally hollow, with a crystalline surface, 

 and covered with metallic silver. The globules act strongly on the mag- 

 netic needle. 



2. Analysis. 

 By ZIPPE. 



Silver 33-20 



Iron . . . . . . 36-00 



Sulphur 30-00 



3. It is found along with other ores of silver, at Joachimsthal in Bo- 

 hemia. 



