The yellow glaze is the colour adopted by the present Tsing dynasty as the Imperial colour. Fine specimens covered with yellow may then be regarded as having been destined principally for the use of the Emperors, but it does not follow that the use of this colour was proscribed in the decoration, either as a yellow or as a partial tint. Blue was one of the highly esteemed colours as well as one of the earliest. We have dealt with blue as an under-glaze decoration. It was not alone used for decorative purposes in drawings of figures, birds, animals, foliage, and landscape, but it was used in various forms as a body colour either on the biscuit itself, before glazing, for with the glaze as a self-colour, as a Celadon, in fact--that is, the blue was applied _in_ the glaze or _in_ the enamel.
We read that in 954 A.D. the Emperor Chin-Tsung ordered some vases to be made which should be "blue as the sky after rain when seen between the clouds," and it is said that his celebrated porcelain was of this blue, fine like a looking-glass, thin as paper, and giving a sound like a musical stone, the only defect being that the feet of the pieces were of a coarse yellow clay. Alas for the romantic story!
The most recent catalogue of the Musée Guimet at Paris, drawn up by the national experts with the assistance of such Chinese experts as were available, states that the story is all a mistake. The word which was translated "blue" should have been translated "green," which brings us back again to Celadon.
During the Sung dynasty (960-1279 A.D.) it appears that a fine red was discovered from which porcelain was made resembling chiselled red jade. This may be the celebrated "_sang de bœuf_," which is red, but, as we have seen, red with qualifications.
The purple or lilac glaze before referred to seems to have been made quite as early as the Sung dynasty, but with this, as with all the other glazes, colour alone is no indication of age.
About the year 1600 there lived that famous potter called Chow, whose fame was obtained by his excellence in skilfully imitating ancient vases. All the records that have come to us show very clearly that from the earliest times the potters were in the habit of copying the works of their predecessors. So well was this continually done that they were able to impose upon the best experts of their own country.