Table 2. Total and relative Fe concentrations of the reference compounds phases based on LCA analysis (uncertainties on the last digit are reported in parentheses).

	C9	C11	C13	C20
Ferrihydrite [FeO(OH)]	0.81 (5)	0.64 (5)	0.64 (7)	0.81 (7)
Hematite (Fe2O3)	–	–	0.07 (4)	–
Siderite (FeCO3)	0.19 (1)	0.36 (7)	0.26 (1)	0.19 (3)