320108
Noms. # Formules.
## SILICIAS ALUMINICO-CALCICUS.
Basis = 3 \2.Ca + 2 \3.Al = C + A
Var. 1: ma........... # {\2.Ca^3 \3.Si^2 + 2\3.Al \3.Si \\ CS + AS
Var. 2: da........... # {\2.Ca^3 \3.Si^4 + 2\3.Al \3.Si \\ CS^2 + AS
Var. 3: a.?.......... # {\2.Ca^3 \3.Si^4 + 2\3.Al \3.Si^2 \\ CS^2 + AS^2
Var. 4: ta........... # {3\2.Ca \3.Si^2 + 2\3.Al \3.Si \\ CS^3 + AS
Var. 5: ta........... # {3\2.Ca \3.Si^2 + 2\3.Al \3.Si^2 \\ CS^3 + AS^2
Var. 6: ta........... # {3\2.Ca \3.Si^2 + 2\3.Al \3.Si^3 \\ CS^3 + AS^3
Basis = 3 \2.Ca + 4 \3.Al = C + 2 A
Var. 1: ma. Zoisite....... # {\2.Ca^3 \3.Si^2 + 4\3.Al \3.Si \\ C S + 2 A S
Var. 2: da........... # {\2.Ca^3 \3.Si^4 + 4\3.Al \2.Si \\ CS^2 + 2 AS
Var. 3: tia........... # {\2.Ca^3 \3.Si^4 + 4\3.Al \3.Si^2 \\ CS^2 + 2 AS^2
Var. 4: ta........... # {3\2.Ca \3.Si^2 + 4\3.Al \3.Si \\ CS^3 + 2 AS
Var. 5: ta........... # {3\2.Ca \3.Si^2 + 4\3.Al \3.Si^2 \\ CS^3 + 2 AS^2
Var. 6: ta........... # {3\2.Ca \3.Si^2 + 4\3.Al \3.Si^3 \\ CS^3 + 2 AS^3
Exemples de quelques silicaies doubles, qui font voir comment les silicates de
mêmes bases peuvent varier quant à la proportion relative de leurs principe
constituants. On y trouve la formule minéralogique au-dessous de la formu
chimique.
11 mêmes bases peuvent varier quant à la proportion relative de leurs principe
constituants. On y trouve la formule minéralogique au-dessous de la formu
chimique.
Noms. # Formules.
## SILICIAS ALUMINICO-CALCICUS.
Basis = 3 \2.Ca + 2 \3.Al = C + A
Var. 1: ma........... # {\2.Ca^3 \3.Si^2 + 2\3.Al \3.Si \\ CS + AS
Var. 2: da........... # {\2.Ca^3 \3.Si^4 + 2\3.Al \3.Si \\ CS^2 + AS
Var. 3: a.?.......... # {\2.Ca^3 \3.Si^4 + 2\3.Al \3.Si^2 \\ CS^2 + AS^2
Var. 4: ta........... # {3\2.Ca \3.Si^2 + 2\3.Al \3.Si \\ CS^3 + AS
Var. 5: ta........... # {3\2.Ca \3.Si^2 + 2\3.Al \3.Si^2 \\ CS^3 + AS^2
Var. 6: ta........... # {3\2.Ca \3.Si^2 + 2\3.Al \3.Si^3 \\ CS^3 + AS^3
Basis = 3 \2.Ca + 4 \3.Al = C + 2 A
Var. 1: ma. Zoisite....... # {\2.Ca^3 \3.Si^2 + 4\3.Al \3.Si \\ C S + 2 A S
Var. 2: da........... # {\2.Ca^3 \3.Si^4 + 4\3.Al \2.Si \\ CS^2 + 2 AS
Var. 3: tia........... # {\2.Ca^3 \3.Si^4 + 4\3.Al \3.Si^2 \\ CS^2 + 2 AS^2
Var. 4: ta........... # {3\2.Ca \3.Si^2 + 4\3.Al \3.Si \\ CS^3 + 2 AS
Var. 5: ta........... # {3\2.Ca \3.Si^2 + 4\3.Al \3.Si^2 \\ CS^3 + 2 AS^2
Var. 6: ta........... # {3\2.Ca \3.Si^2 + 4\3.Al \3.Si^3 \\ CS^3 + 2 AS^3