Table 2.

Average major and minor elements for pyroxene composition determined with EPMA

	QUE 97008, 12			MET 00452, 16			NWA 8649			NWA 8276
	c51	c61	c143	c150	c19	c111	c17 (core)	c17 (rims)	c87	c7	c69	c88
SiO2	54.18	54.43	51.78	52.60	55.58	56.09	55.04	56.35	54.91	52.64	55.96	55.63
TiO2	0.19	0.55	0.58	0.13	0.13	0.14	0.16	0.19	0.15	0.51	0.41	0.04
Al2O3	2.75	2.71	2.55	2.16	1.58	1.53	1.98	1.74	2.56	2.57	1.91	0.40
MgO	30.04	29.30	22.93	27.45	32.47	34.23	31.57	34.35	32.83	25.72	34.14	31.40
FeO	8.20	4.94	14.43	12.36	7.22	5.86	7.81	4.78	5.75	10.76	2.01	10.31
CaO	2.66	6.65	5.26	2.60	1.57	1.28	1.50	1.77	1.86	5.23	3.75	0.56
Na2O	0.01	0.01	0.00	0.01	0.00	0.00	0.00	0.00	−0.01	0.00	0.00	0.00
MnO	0.24	0.13	0.52	0.35	0.25	0.21	0.48	0.14	0.16	0.30	0.03	0.21
Cr2O3	1.52	1.08	1.09	1.18	1.31	1.00	1.19	0.84	1.48	1.24	1.04	0.78
Total	99.80	99.80	99.16	98.84	100.09	100.32	99.74	100.17	99.67	98.96	99.27	99.32
Si	1.926	1.921	1.921	1.924	1.950	1.946	1.944	1.947	1.927	1.923	1.941	1.980
Ti	0.005	0.015	0.017	0.004	0.003	0.004	0.004	0.005	0.004	0.014	0.011	0.001
Al	0.115	0.113	0.112	0.093	0.065	0.063	0.082	0.071	0.106	0.110	0.078	0.017
Sum	2.046	2.049	2.049	2.021	2.019	2.012	2.030	2.023	2.036	2.047	2.030	1.998
Mg	1.591	1.542	1.265	1.497	1.699	1.770	1.662	1.769	1.717	1.400	1.765	1.666
Fe	0.244	0.146	0.449	0.378	0.212	0.170	0.231	0.139	0.169	0.329	0.058	0.307
Ca	0.101	0.251	0.211	0.102	0.059	0.048	0.057	0.066	0.070	0.205	0.140	0.021
Mn	0.007	0.004	0.016	0.011	0.007	0.006	0.015	0.004	0.005	0.009	0.001	0.006
Cr	0.043	0.030	0.032	0.034	0.036	0.027	0.033	0.023	0.041	0.036	0.029	0.022
Na	0.001	0.001	0.000	0.001	0.000	0.000	0.000	0.000	−0.001	0.000	0.000	0.000
Sum Oct	1.987	1.973	1.973	2.022	2.013	2.021	1.997	2.001	2.001	1.979	1.993	2.023
Mg#	86.7	91.4	73.5	79.8	88.9	91.2	87.8	92.7	91.1	81.0	96.8	84.5
Enb	81.9	79.4	65.2	75.3	85.9	88.8	84.6	89.5	87.6	72.1	89.9	83.3
Woc	5.2	12.9	10.9	5.1	3.0	2.4	2.9	3.3	3.6	10.5	7.1	1.1

^aMg# = Mg / (Mg + Fe) mol%.

^bEn = Mg / (Mg + Fe + Ca) mol%.

^cWo = Ca / (Mg + Fe + Ca) mol%