CATALOGUE OF MINERALS. 



15 



Name. 



System of 

 crystallization. 



2(;9. 

 270. 

 271. 

 272. 

 273. 

 274. 

 275. 

 27tJ. 

 277. 

 278. 

 279. 

 2b0. 



Leucite 

 Nepheline * 

 Cancrinite * 

 Anorthite 

 Andesine * 

 Barso\wite 

 BytOAvnite ? 

 Labradorite * 

 Oligoclase * 

 Albite * 

 Orthoclase * 

 Petalite * 



(Na,K)'Si + 2SlSi 6 



Na2 Si + 2A1 Si + (Na, Ca) C+ E[ 6 



(Na, K, Ca, Mg) » gi 4- 3Xrgi . 5 



(Ca,Na)*Si2 + 3XlSi^ 5 



Ca3Si'+3XrSi 5? 

 Ca^Si^+SSrSi 



(Ca, Na)Si + XlSi 5 



(Ca, Na) Si + Al Si^ 5 



Na Si + XI Si3 5 



K §i 4- Xl 5i' 4 



(Li,Na)''Si^ + 4;ilSi« 5? 



* And Xl Si J. In Topaz part of the oxygen is replaced by fluorine, 

 t And Al Sij. Rammelsberg writes the formula (K, S^) +Si° 



