Analysis of Argentine and Steatite. 333 



E. The liquor (D). when treated with an excess of caus- 

 tic potash, afforded 0.72 grammes of magnesia on 3 grs. or 

 24.0 per 100. 



The constituents of this mineral are, therefore, 



Per 100 parts. 



A. Water - - 1.033 Containing oxygen, 



B. Silica - 56.333 



C. Proloxide of iron 4.300 



C. Alumina - 1.666 



D. Lime - 10.666 

 £. Magnesia - 24.000 

 C Protoxide of chrome a trace. 



Art. XVII. — Analysis of Argentine and Crystallized Steatite, 

 by Professor Dewey. 



Argentine. 



At the lead-mine in Southampton, Mass. a mineral is 

 found in considerable quantity, which is a nearly pure car- 

 bonate of lime, and has the following characters. It gen- 

 erally consists of undulated, not parallel, laminae, of a pear- 

 ly shining lustre, often of a beautiful silvery white. Some- 

 times it is in thin plates, which intersect and form small 

 cells, containing crystals of calcareous spar. The thin la- 

 minas are translucent. Sometimes it is less laminated and 

 more compact, with less lustre, and the cross fracture is 

 slightly granular. It was supposed to contain magnesia, 

 and three years since I examined it without detecting any 

 of this earth. It was then laid by as a beautiful carbonate 

 of lime, without a suspicion of its being one of the sub-spe- 

 cies of this mineral. The characters prove it to be Argen- 

 tine. 



It occurs on very compact granite, and is also associated 

 with fetid quartz, which is found in small masses in it and 

 upon it. When it joins the quartz it is more compact and 



