Fernando Nieto
Characterization of coexisting NH₄- and K-micas in very low-grade metapelites

TABLE 2. Chemical composition of rocks containing tobelites

 

Major elements (% weight)

Samples	SiO2	Al2O3	TiO2	FeO	Fe2O3	MgO	CaO	Na2O	K2O	P2O5	LOI	Total
Ge-6	54.3	28.7	1.12	0.20	0.64	0.50	0.33	0.33	3.56	0.18	9.93	99.79
Ge-7	53.4	29.3	1.15	1.50	0.76	0.70	0.23	0.27	3.68	0.13	9.00	100.12
Ge-8	60.1	24.0	0.96	0.30	0.60	0.48	0.16	0.34	4.04	0.10	8.77	99.85

 

Samples	Be	B	Sc	V	Cr	Mn	Co	Ni	Cu	Zn	Ge	As	Br	Sb	Cs
Ge-6	9	254	17	184	93	51	5	25	67	67	0	6	2	0.7	31
Ge-7	10	248	21	251	120	123	11	46	45	68	15	12	2	0.6	30
Ge-8	7	128	14	149	79	40	11	21	31	58	0	16	2	0.8	25

 

Samples	La	Ce	Nd	Sm	Eu	Tb	Yb	Lu	Hf	Ta	W	Pb	Th	U	Rb	Sr	Y	Zr	Nb	Ba
Ge-6	54	99	43	8.7	1.6	1.2	2.8	0.4	4.0	2	3	5	16	9.4	251	69	53	152	25	985
Ge-7	61	116	47	8.1	1.7	1.0	2.6	0.4	3.4	1	3	5	18	7.5	246	48	38	140	12	1050
Ge-8	54	103	44	7.9	1.6	1.1	3.3	0.5	6.1	1	3	7	17	8.6	238	27	62	244	25	728