i24 On the Analyses of the Chromate of Iron, ^c. 



brought from the Valais, which I recognised from its struc- 

 ture and physical properties to be a variety of the epidote'/ 

 although it differed in its external characters from the cry- 

 stals of this species hitherto observed. M. Laugier found 

 that the respective quantities and qualities of its component 

 principles were the same as in the epidote of Arendal, and 

 in that of France, analysed by M. Vauquelin and M. Des- 

 costils. 



The same variety also exists in Carinthia and in some 

 of the neighbouring countries ; and M. Werner has since 

 given the name of zoysite to it in honour of barofi Zoys. 

 The distinction which M. Werner establishes between this 

 substance and our epidote is in some measure a consequence 

 of the nomenclature adopted by this celebrated naturalist ; 

 for he gives to the epidote ihe name of Pistazite (Pistachio 

 stone) because it is g'^nerally of a more or less deep green. 

 Now this name seems to exclude the zoysitc, the colour of 

 which is gray, brown, or brownish yellow, but never green ; 

 at least it is so in those specimens we have seen. 



M. Laugier has been informed that Messrs. Klaproth and 

 Bucholz have recently analysed the zoysite ; and the follow- 

 ing are their results, compared with those of the French 

 chemist. 



KLAPROTH. LAUGIER. BUCHOLZ. 



Gray Epidote, said to be The same Substance. The same Substance. 

 Zoysite. 



Silex - - - - 45 37 40*25 



Alumine - - - 29 • ^Q'Q 30*25 



Lime - - - - 21 • 20 22*5 



Oxide of iron - 3 13 4*5 



Oxide of manganese o 0-6 0*0 



Water - - - - o 1*8 2 



Loss - - - - 2 1 0-5 



loa 100 100 



If wc compare these three results either with each other 



or with the others which have for their objects the epidotes 



of Norway and France ; and if on the one hand wc consider 



tiie- agreement which exists, between chemistry and the 



geometry 



