1826.] affecting Chemico-Minerahgical Si/stems. All 



3. Silicates teith an alkaline base, tcith silicates 



of magnesia {occasionally replaced by the 



oxidulei of iron or 7nanganese) and silicate 



of alumina. 

 Talc. 



Agalmatolite. 

 Pimelite. 

 Cimolite. 

 Chlorite. 

 Green earth. 

 3Iicas. 



a. — with base of potassa. 



b. — magnesian. 



c. — with base of potassa and lithia. 

 Gieseckite, 



Finite. 

 Fahlunite. 



4. Silicate with an alkaline base, tailh silicate 



of iron. 

 Aclimite N S^ + 2 F S'' 



5. Silicates of lime with silicates of magnesia, 



often replaced by oxidulous iron, more 

 rarely by oxydulous manganese ; and the 

 silica sotnetimes replaced by alumina. 

 Pyroxene. 



a. White pyroxene C S'^ + 31 S'^ 



b. Green pyroxene C S'' + ^H S^ 



c. Hedenbergite ,.., C S° + / S» 



M 



d. Manganesiferous C S^ f 



mr, 



e. Augite CS- + ^H ^2. 



Amphibole. 

 fl. Grammatite C S3 + M S^ 



b. Actinote C.S- + ■^'\s' 



c. Hornblende CS^+^Y)- S^^^ 



6. Silicates of lime, magnesia, and the oxydules 



of iron and manganese. 



Ilvaite CS + 4/S 



Cronstedtite mnS + 6fS + 9 ^q 



PyrosmaHte mn S'' + f S* 



Chrysolite (olivine) ^H S 



I>iallage f g-^ + 3 MS' 



Hypersthene y^a + jfj gt 



7. Siliotttes of lime often replaced bymagnesia, 



or by the oxydules of iron or manganese ; 

 teith silicates of alumina, occasionally re- 

 placed by peroxide of iron, 

 Epidote. 

 a- /ioisite CS + 2 AS 



b. Pistacite f ( ■* + ' ^ ■S 



Idocrase. 



a. Vesuvian (common), 



b. Loboite (containing magnesia). 



c. Cyprina (cupriferous). 

 EHsonite. 

 Garnet, 



f >s* 



■in J 



