CHEMICAL FORMULAS OF MINERALS. 



345 



Kreittonite," (var. of Spinel), 

 Halloysite (161), 

 Heulandite (164). 

 Stilbite (165), 

 Apophyllite (165), 

 Laumontite (166), 

 Natrolite (166), 

 Scolecite (167), 

 Thomsonite (167), 

 Harmotome (168), 

 Analcime (168), 

 Chabazite (169), 

 Prehnite (170), 

 Sillimanite (172), 

 Kyanite (175), 

 Andalusite (174), 

 Staurotide (174), 

 Leucite (175), 

 Orthoclase (176), 

 Albite (177), 

 Labradorite (178), 

 Nepheline (179), 

 Scapolite (180), 

 Meionite (181), 

 Petalite (182), 

 Epidote (182), 

 Allaiute (183, 207), 

 Idocrase (184), 

 Garnet (184), 

 Tourmaline (187), 

 Axinite (190), 

 Iolite (190), 

 Muscovite (191), 

 Biotite (193), 

 Phlogopite (193), 

 Topaz (194), 

 Beryl (197), 



(2n, Fe) (3tl, Fe) 

 ^l'Si-|-3fl (in part) 



6a§i+2fcli3i 3 +5fi 

 Ca'Si+A : rSi 3 -f6fl 



6a, &, Si, fi, F. 



Ca 8 §i*-f32fcl§i*+-2fi 



tfagi+£lgi-f-2fl 



6a§i+2tl§H-8fi 



R 3 gi+3£lgi+7S 



BaSi+£lSi 2 +5fi 



STa8gi*+3*l§i 2 + 6fi[ 

 fc»8i 8 +32fcl8i 8 -|-18fi[ 

 2<Vgi+3£lSi+fi 3 gi 

 2tiSi*; (partly XlSi?) 



2tlSi* 

 XlSi* 



£»Si»+82fclSi* 



(£+2fcl)§i«=fcSi+3tlSi» 



(Na-r-£l)gi 4 =Nagi-f-£lgi* 



(<Vf-2fcl)Si*=CaSi+2tl5i 



(Na-f £l)Si£=Na* Si -4-2^:18 i 



(iR n 44AM)giWl 3 Si+£l2§ 3 



a<V+££l)S'i=Ca 3 Si+2£lSi 



( ^ 3 +t*l)§i 4 =J5 3 Si 4 -f4itlSi< 



(ifef+f3tI)Si=ft3Si-i-2*l§i 



(£ft 3 +f£l)Si=3R 3 Si+2£lSi 



(i$ 3 -f i*l)gi=R3§i +2tlSi 



(R 3 ,£l,B)gi* 



(R 3 ,B,B)gi 



(iR 3 +^l)Sif=ft3g i |- + 3^ 1 s i f 



(T^ 3 +iP)Si^=R 3 Sii+ 1 28 Sit 



(ffc 8 +f£l)Si=SR^-f2£lSi 



3tlSi* with F replacing part of 

 (i£e+ frXl)§l*= J.-S.2+ AlSia 



