65 



TAB. CCCXXXVII. 



STANNUM oxygenizatum. 

 Oxide of Tin (in veins in Schist or Killas). 



Class 3. Metals. Order I. 



Gen. 5. Tin. Spec. 1. Oxide. 



Div. 3. Amorphous, 



Syn. Tin veins in the Killas, or argillaceous Schist. 

 Kirw. 1. 237. 



It is very instructive to see the form of "the Tin veins and 

 their direction with regard to the formation of the Schist 

 or Slate, they being either straight, or curved in a remark- 

 able manner, and usually crossing the laminae of the Slate. 

 The upper specimen came from St. Agnes in Cornwall, 

 and consists of the coarser Killas*: the oblique position of 

 the veins in the larger specimen shows it to be from a 

 lower part of the primitive Slate formation than the under 

 figure, in which they are finer and more parallel, being of 

 a rather later formation. 



* Killas is the Cornish term for the primitive Schist in which Tin is found. 



VOL, IV. 



