344 Solvents Analysis of the Pytoxene. 



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

 ding experiments, must therefore constitute a new species 

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

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

 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 jVeiv-Haveri, Conn. By George T. Bowen, 

 of Providence. 



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

 imbedded in green serpentine marble. It? 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 is 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. 



Analysis. 



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 .468 per 

 100. 



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 100. 



* Done in the Laboratory of Yale College. 



