So far as my reading extends, the nature of the black varnish of the ancient Greek and Etruscan vases is still undetermined.

From the experiments I have made, operating on very small quantities, abraded from vases which were taken from tombs in the Ionian Islands, I have been led to the conclusion, that it is a vitreous matter, coloured by black oxide of iron, probably mixed with particles of metallic iron, to which its peculiar lustre may be owing.