Bozoen^s Analysis of a variety of JVephrite. MT (^iAf 



arated in this manner, when washed and calcined, weighed 

 44.688 grains. 



C. The solution (B), was neutralized with ammonia and 

 treated with the hydrosulphate of ammonia. — The precip- 

 itate when ignited and calcined with nitric acid weighed 

 2.313 grains. When fused with caustic potash, it imparted 

 to it a tinge of green, giving indications of a trace of man- 

 ganese. The oxide of iron remaining after the action of 

 caustic potash, amounted to 1.747 grains. We have then 

 by difference aluraine equal to 0.562 grains. 



D. The lime was precipitated from the liquor (C), by 

 the addition of oxalate of potash; when calcined it weighed 

 4.250 grains. 



E. To the remaining solution, (D), after the separation 

 of the lime, caustic potash was added in excess, and the 

 fluid boiled. The magnesia separated by this treatment, 

 when washed and calcined, weighed 34.631 grains. 



F. 250 grains of the mineral were introduced into a small 

 porcelain retort which was connected with the mercurial ap- 

 paratus, and kept at a red heat during one hour. A portion 

 of water distilled over, but no carbonic acid was obtained. 



The composition of this mineral is therefore, 



Per 100 Parts. 



A. Water 13.417 containing oxygen 11.17 



B. Silica 44.688 22.47 



C. Alumine 00.562 



C. Oxide of Iron 01.747 



D. Lime 04.250 01.09 



E. Magnesia 34.631 13.40 



G. Oxide of Manganese a trace 



99.295 

 100.000 



000.705 Loss. 



On comparing the results of the preceding experiments 

 upon this substance, with the analyses of Nephrite which 

 have been hitherto published, we find a considerable differ- 

 ence in chemical composition; the Smithfield mineral con- 

 tains a much greater proportion of water, and only a very 

 small quantity of alumine. It diffe'^ s from Nephrite also in 



