Composition Chemical Analysis Has Shown Several Of The Blues To Be

: ON COLOURS AND COLOURING.

oxide of copper with a small proportion of iron; none containing cobalt.

There is little doubt, however, that the most brilliant specimens--those

which retain all their original force and beauty in the temples of Upper

Egypt after an exposure of three thousand years, consist of

ultramarine--the celebrated Armenian blue, possibly, of the ancients.



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