332 Mr. Seyberfs Analysis of Glassy Actynolite. 



grammes; but as the protoxide of iron contained in the 

 mineral must, during the calcination, have passed to the 

 state of peroxide, and as the absorption of oxygen, estima- 

 ted by calculation, is 0.01 1 grammes, therefore the mois- 

 ture expelled by calcination amounts to 0.031 grammes on 

 3 grammes, or 1.033 per hundred. 



B. The calcined mineral {A) wae exposed to a red heat 

 during thirty minutes, in a silver crucible, with 9 grammes 

 of caustic potash. The cold mass was of a pale green co- 

 lor; it communicated to the water with which it was treat- 

 ed, a lemon yellow color, thus indicating a trace of chrome. 

 The mixture was treated, in the usual manner, with an ex- 

 cess of muriatic acid, and the yellow solution thus produc- 

 ed, was evaporated to a dry gelatinous mass, which was 

 treated with diluted acid and again moderately evaporated. 

 The residue was treated with more water, and the solution 

 was filtered ; the silica collected on the filter, after being 

 washed and calcined, weighed 1.69 grammes on 3 grammes, 

 or 56.333 per 100. 



C. After the liquor {B) was neutralized with caustic pot- 

 ash, on the addition of the hydro-sulphate of potash, a black 

 precipitate was formed, which, after being washed and cal- 

 cined with nitric acid, weighed 0. 1 9 ; this precipitate, when 

 treated with caustic potash, was found to consist of 0.14 

 grammes of peroxide of iron, and 0.05 grammes of alumine, 

 by difference 1.666 per 100. Owing to the green color of 

 the mineral, the iron must be estimated as a protoxide, 

 and the 0.14 grammes of peroxide are equivalent to 0.129 

 grammes of protoxide on 3 grammes, or 4.30 per 100. 

 The alkaline liquor holding the alumine in solution, 

 appeared to be yellow from chrome contained in the min- 

 eral ; to detect the chrome, the alumine was precipitated, 

 by exactly neutralizing the liquor with muriatic acid; on 

 the addition of acetate of lead, there was produced a precip- 

 itate of muriate of lead, intermixed with a yellow precipi- 

 tate of chromate of lead; to another portion of the Hquor, 

 nitrate of silver was added ; the muriate of silver was like- 

 wise intermixed with a red precipitate of chromat of silver, 

 but the chrome seemed to be very trifling. 



D. When oxalate of potash was added to the liquor (C) 

 it occasioned a white precipitate, which, after a strong cal- 

 cination, afforded 0.32 grammes of lime on 3 grs. or 10.666 

 per 100. 



