TURCIUOIS STONE. 187 



which were the most coloured and the most hard, and I sub- 

 mitted them to the following experiments : 



A, — 100 parts of turquoises, reduced to powder, were intro- Analysis solu- 

 duced into a small retort: and 300 parts of nitric acid, at ^^^^^ cTrbonS*^ 

 36 degrees, were poured in. After some time, a slight efFer- acid escaped, 

 vescence appeared, which lasted till the solution was com- 

 plete. The gas being collected in the pneumatic apparatus 

 with mercury, presented all the characters of carbonic acid 

 gas. 



B. — This nitric solution is white, and of the consistence of 



syrrup. It was then evaporated to dryness, and the remaining 



matter made red-hot in a crucible of piatina. 



C. — The calcination had scarcely changed its colour. ^'^e dissolved 



.,.,,. -11,1 maucr was a 



This substance was again dissolved in water, acidulated phosphate. 



with nitric acid, with the intention of separating the iron, 



which might exist in the state of oxide. But the whole was 



entirely dissolved, which evidently proves that the iron was 



neither in the state of red oxide nor in that of nitric, but in that 



of phosphate. 



D. — Ammonia in excess was poured on the liquor C, which Small ponion 

 gave a white precipitate of considerable bulk. This precipi- 

 tate, after washing and drying, was treated with concentrated 

 liquid pot-ash, which dissolved a certain quantity. The liquor 

 of the non-dissolved portion was afterwards separated from 

 the liquor, and muriate of ammonia added, which separated a 

 white substance, possessing all the properties of alumine. This 

 substance, after the calcination, weighed one part and a 

 half. 



E. — The portion dissolved by the pot-ash was also calcined, 

 and its weight proved to be 82 parts. 



F. — Being desirous of ascertaining whether the liquor, from Lime, 

 experiment D, did not contain lime in solution, carbonate of 

 ammonia was poured on the fluid, and a precipitate was ob- 

 tained, which, being slightly dried and heated, was found to 

 be carbonate of lime, its weight was 8 parts. 



G. — The supernatant Hquor was afterwards evaporated, but 

 it aflforde! no precipitate ; whence it may be concluded, that - 

 it contained n ^ magnesia. 



H. — Being per-; laded beforehand that the precipitate E !''<'"• 

 contained phosphates, it was treated wifr- the sulphuric acid. 

 The matter was afterwards washed, and the waters being put 



together. 



