Cobalt Green

: ON THE SECONDARY, GREEN.

Rinman's Green, Vert de Zinc or Zinc Green. True cobalt green is made by

igniting a very large quantity of carbonate of zinc with a very small

quantity of carbonate of cobalt. To give a green tint to an enormous

proportion of the former, an inappreciable amount of the latter will

suffice. Some samples which were analysed, consisted almost entirely of

zinc, there being only two or three per cent. of cobalt present. This

green presents an example of a pigment being chemically good and

artistically bad, or at least indifferent. It is a moderately bright

green, apt to vary in hue according to the mode of manufacture,

permanent both alone and compounded, but so sadly deficient in body and

power, as to have become almost obsolete. With other physical defects,

and a colour inferior to the chrome oxides, cobalt green has never been

a favourite with artists, though justly eulogised by chemists.



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