Swiss Journal of Geosciences

Table 4 Composition of amphiboles in eclogite facies SW9

From: The Theodul Glacier Unit, a slab of pre-Alpine rocks in the Alpine meta-ophiolite of Zermatt-Saas, Western Alps

	Act	Act	Hbl	Hbl	Hbl
SiO₂	55.2	53.96	45.96	48.78	49.08
TiO₂	0.01	0.05	0.2	0.22	0.13
Al₂O₃	3.23	5.79	6.65	7.77	9.21
FeO	7.88	6.74	20.51	16.2	12.97
MnO	0.05	0.03	0.39	0.47	0.04
MgO	18.01	17.78	10.59	11.59	12.88
CaO	11.02	9.67	9.94	10.16	9.95
Na₂O	1.26	2.12	0.71	1.30	1.98
K₂O	0.07	0.19	0.07	0.12	0.11
Cl	0	0	0.02	0.01	0.01
F	0.23	0.26	0.14	0.15	0.24
Total	96.98	96.67	95.24	96.92	96.71
Si	7.805	7.617	7.112	7.235	7.173
Ti	0.000	0.005	0.023	0.025	0.014
Al	0.538	0.963	1.213	1.358	1.586
Fe²⁺	0.932	0.796	2.654	2.009	1.585
Mn	0.006	0.004	0.051	0.059	0.005
Mg	3.796	3.742	2.443	2.563	2.806
Ca	1.670	1.463	1.648	1.615	1.558
Na	0.345	0.580	0.213	0.374	0.561
K	0.013	0.034	0.014	0.023	0.021
Sum cations	15.105	15.203	15.372	15.260	15.310
Al(IV)	0.195	0.383	0.888	0.765	0.827
Al(VI)	0.343	0.580	0.325	0.593	0.760
Sum Al(VI), Ti, Fe, Mn, Mg	5.272	5.509	6.385	6.014	5.997
X_Mg	0.803	0.825	0.479	0.560	0.639
Sum Ca, Na, K	2.028	2.077	1.875	2.011	2.140

Total includes traces of Cr. X_Mg = Mg/(Mg + Fe)

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