ANALYSIS OF SOME STEATITES. J^-o 



Analysis of the yelloivish compact talc fspeckstein.) Bildstein 



1. A hundred parts of this stone strongly calcined lost calcine 1- 

 5 parts. 



2. Heated afterward with twice its weight of potash in j^pg^gj ^jji. 

 a silver crucible no fusion took place, but the matter was potash j 

 gV'eatly increased in bulk, and had become homogeneous. 



3. This was diffused in water, and dissolved in muriatic 



acid. The solution, being evaporated, became gelatinous muriatic add - 

 toward the end of the operation. 



4. The matter beinsj dried, and v/ashed, a white powder .... 

 remained, which, after calcination, weigned 56 parts. 



5. The silex having: been separated by llxiviation, the . . 



? „ • c • • -1 precipitated 



liquor was mixed with a small quantity ot mm^iatic acid, with ammonia; 



and ammonia was afterward poured in, which formed in it a 



copious white flocculent precipitate. 



6. The liquor being filtered, the precipitate was washed treated with 

 and dried. This was alumine, and weighed 30 parts. The sulphuiic acid; 

 alumina dissolved entirely in sulphuric acid, and its solu- 

 tion, saturated with the recpisite qxi an tity of potash, af- 

 forded very pure alum : but the mother water, evaporated 



afresh, yielded 5f parts of sulphate of lime crystallized in 

 needles. Thus with the assistance of the alumine the am- 

 monia precipitated the lime from its solution in muriatic 

 acid. 



7. The liquor from which the alumine had been separa- ^ i . t, 

 ted gave no precipitate with carbonate of soda, even assisted of soda, but 

 by long boiling. The speckstein therefore contains no "j"^ ^^ . ,^ 

 iuagnesia, like the two preceding varieties. 



But in recapitulating the products of this analysis we „ ^^ . ^ , .^ 

 find only 93 parts; namely analysis, 



Sile.K .■.-.... .... 5G 



Alviniine 29 



i.,ime ^y 



Iron 1 



Water" • . . . ^ • 5 



93 

 A loss so considerable, which is not common in such j .^j^ ^^^ great, 

 analyses cavefuHy executed, led me to suspect, that- the 



