Mineralogical Notices, 217 



a grayish green glass. With salt of phosphorus gives evidence of 

 chrome, and with soda, a manganese reaction- Composition of 

 the chlorite of the Col de Pertuis 



Si ^1 '^r Pe S[n Mg(bydiff.) Ga 



33-23 14-78 1-49 6'28 I'SQ 30-76 1-86, ign. 10-21 = 100 



Bischof has shown that a solution of bicarbonate of magnesia 

 ^ will transform, even when cold, sihcate of lime recently prepared 



into carbonate of lime and silicate of magnesia; and with this 

 fact, M. Delesse observes that the change of garnet into chlo- 

 rite may be explained. The pseudomorphosis has taken place 

 over a wide extent. 



Chrysotile occurs in seams havina^ a delicate fibrous texture : 

 It is translucent, and the fibres separated are transparent; color 

 oil-green, usually clear, sometimes olive-green ; lustre silky. 

 G. =2-223. B.B. yields water; on platinum wire, it gives a 



bright light aiid fuses with difficulty to a glass slightly brownish. 



4 



Dissolves with borax or soda. Composition : 



Si Si f'e ]VIi,-(bydiff.) fi 



41-58 0-42 1-69 4261 1370 — 100 



The picrolite of Stromeyer has the same composition. 



Nematite occurs at Xettes in the Yosges^ and also at Saint 

 Sabine. Brvdte is found at Goujot. 



The Serpentine is of various qualities and colors. Analyses: 



, ^, Si Si «r te iln 6a ^Efg (by diif.) i-n. 



1. Blackish-f^Teen, Liesey, 40'83 0-92 0-68 1Z2 trace 1-50 37'98 10-'70=100 



2. Maroon-red, Goujot, 42-26 1-51 7*11 080 38-90 9-42=100 



Specific gravity of the first 2749. 



In the second analysis, the alumina as obtained included some 

 chrome and oxyd of manganese. The serpentine of Goujot 

 takes a fine polish and sells at 54 francs the square meter. 



The author next discusses the relative age and the origin of 

 the minerals and serpentincj giving many views of interest. He 

 observes that of the minerals which have been formed in serpen- 

 tine, those most magnetic (as those rich in iron) have remained 

 in the paste, while those that are diamagnetic have been separa- 

 ted into fissures, so as to form veins or amygdaloids. The mag- 

 i^etic and diarnagnetic forces, according to this view, have acted 

 an important part in the development and distribution of the in- 

 cluded minerals. 



Picrolite of ^'iVe^/a.— Analysis by Dr. List, (Ann. d. Ch. u. 

 l^harra., Ixxiv, 241): 



Si Ififg fe fi 



44-606 39-748 2-631 2*576 = 99-561 



Leuchtenhergite. — Breithadft (Pogg. Ann., Ixxx, 577) ob- 

 serves that the specimens of Leuchtenbergite are evidently more 

 ^ less altered by exposure or otherwise, and this is farther proved 

 ny the fact that Komonen obtained but 8*62 per cent, of water, 



Second Series, Vol. XII, No. 85.— Sept., 1851. 28 



