PHYSIOGRAPHY. 279 



Witherite Wolfram. 



position. The 'composition repeated, so as to give rise to 

 a six-sided prism, as in Arragonite. Globular, tuberose, 

 reniform, botryoidal shapes : surface rough, uneven, and 

 drusy ; composition granular, often strongly coherent. 

 Massive: composition either granular, or columnar; more 

 frequently the latter. 



1. Before the blow-pipe, it decrepitates slightly, and melts easily into 

 a transparent bead, which loses its transparency on cooling. It is solu- 

 ble with effervescence in dilute nitric acid. 



2. Analysis. 

 By BUCHOLZ. 



Baryta 79-66 



Carbonic acid 20-00 



Water 0-33 



3. It occurs in veins traversing limestone which rests upon red sand- 

 stone ; it is also found in lead-veins traversing greywacke, and in irreg- 

 ular beds along with Ankerite in clay-slate. 



4. It exists abundantly in the counties of Durham, Westmoreland, 

 Lancaster, and Salop, (England) in veins; also near Neuberg in Stiria 

 in irregular beds. It has been mentioned from Hungary, Salzburg, Si- 

 beria, Sicily, and other places. . 



5. It is a violent poison. 



(See Kyanite.) 



WoLCHOUSKOIT. 



Massive : composition impalpable. Fracture conchoid al. 

 Color bluish green. Streak similar to color. Opake, adheres 

 slightly to the tongue. 



1. It consists of silica, alumina, oxide of chrome and water. 



2. It is found in Siberia. 



WOLFRAM. Prismatic Baryte-Ore. 



Primary form. Oblique rhombic prism. M on M = 

 98 12'. " 



