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The pattern of analysis by X-ray fluorescence of (a) the black pigment of magnetite (Fe3O4), (b) white pigment of calcite (CaCO3), (c) the yellow pigment of orpiment (As2S2), (d) the red pigment of hematite (Fe2O3), (e) the orange pigment of orpiment (As2S2) and hematite (Fe2O3), (f) the blue pigment of Egyptian blue (CaCuSi4O10), and (g) the green pigment of malachite (Cu2CO3(OH)2).
