Commentary Page 174



	COMMENTARY

	variety, and the results of analyses of Greek iron oxide pigments, suggest that it was also applied to pale red or even pink pigments consisting of little more than clay or chalk colored with ferric oxide. On examining eight such pigments that were found on objects excavated at Athens, Midgley³⁷⁹ discovered that six of them contained less than twenty per cent of ferric oxide, and that one of them, a pink pigment, contained only about three and a half per cent. Since no special name appears to have been applied to red iron oxide pigments artificially produced by roasting yellow ochre, or to the pale red or pink pigments, it is very likely that they went by the same name as red ochre itself. Red ochre and other red iron oxide pigments occur so frequently on ancient Greek objects of all sorts, and so many vessels containing the remains of these pigments have been found, that they were probably used in Greek times more extensively than any other kind of pigment. Probably their great abundance and low cost were the principal reasons for their widespread use. 51. yellow ochre. It seems reasonably certain that the word ωχρά invariably designated what today is called yellow ochre, a mixture of hydrated ferric oxide with clay, sand, and other impurities. The information in sections 53 and 54 about the conversion of ωχρά into μίλτος by roasting is almost decisive for this identification. Moreover, the chemical examination of ancient pigments of yellow ochre that were found in the excavations of the Agora at Athens has shown that they have the same composition as the mineral now called yellow ochre. Theophrastus discusses the occurrence and the sources of red ochre, but he says very little about the sources of the yellow ochre used in his day. Probably this is because the principal source of the best yellow ochre was so well known to him and to his contemporaries that he considered it quite unnecessary to mention it. Most of the later writers on ancient pigments mention Attica as the source of the best yellow ochre. Dioscorides³⁸⁰ actually implies that it was the only satisfactory source. Pliny³⁸¹ names other ³⁷⁹ S. W. Midgley, "Chemical Analysis of Ancient Athenian Pigments," Senior thesis, Princeton University, 1936, pp. 14-21. ³⁸⁰ V, 108 (Wellmann ed., V, 93). ^8S1XXXIII, 158-59.

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