344 Boweti^s Analysts of the Pyroxene. 



fluo-silicic acid in a native state ; the subject of the prece- 

 ding experlmeiits, must therefore constitute a new species 

 in our nuneralogical system, and I propose to call it Maclu- 

 reite. as a mark of my respect and esteem for Mr. Wni» 

 Maclure, to whose efforts we are much indebted for a know- 

 ledge of the Mineralogy and Geology of the United States, 



Art- XVI. — Analysis^ of the Pyroxene Sahlite^ from the 

 vicinity of Kew-Haven^ Conn. By George T. Bowen, 

 of Providence. 



This mineral is found 2 or 3 miles west of New^-Haven, 

 imbedded in green serpentine marble. Its colour is grayish 

 green; the colour of its powder is light gray — its structure 

 is crystalline — easily breaking into rhombic fragments; no 

 distinct crystals, have, however, been observed — its fracture 

 in one direction is foliated, having a vitreous lustre ; the cross 

 fracture is uneven and nearly dull — it i* translucent at the 

 edges — its hardness is nearly equal to that of augite — it 

 is not magnetic — before the blowpipe it Is fusible with diffi- 

 culty into a dark coloured globule — its specific gravity va- 

 ries from 3*127 to 3.294. 



Jinalysis, 



A. 50 grains of the mineral having been carefully freed 

 from foreign substances, were reduced to an impalpable 

 powder, and exposed during one hour to a high red heat in 

 a platina crucible. The powder after calcination was a 

 shade darker than before, and weighed 49.766 grains. The 

 loss by calcination was therefore ,234 grains, or •463 per 



1 00. 



B. After calcination the mineral was fused with three 

 times its weight of caustic potash in a silver crucible and 

 kept a red heat during one hour. The mass after fusion 

 was of a grass green colour, which it imparted to the wa- 

 ter used to detach it from the crucible- Muriatic acid was 

 added in excess, and the fluid evaporated to dryness. It 

 was then treated with water acidulated with muriatic acid, 

 and the silex separated by the filter; when washed and cal- 

 cined, it weighed 26.562 grain or 53.124 grains per 1 00. 



Done in the Laboratory of Yak College. 



