PORCELAIN DECORATED
former with one of the latter; the average blue of about equal parts, and this came out of the kiln with each stroke of the brush clearly defined. The first-class blue mixed with much water and spread over the surface in mass, gave a pure and transparently bright tint.
The Tao-lu states that ten ounces of the imported blue in its unrefined state cost three dollars. Thus the cost after refinement was more than a dollar and a half per ounce. A special class of experts devoted themselves to judging its quality. To the choicest grade they gave the fanciful epithet "blue of the head of Buddha." Nothing is known as to the exact composition of this Mohammedan blue. The native Chinese mineral, with which the potters of the seventeenth and eighteenth centuries produced beautiful results, has been analysed by M. Salvétat. His result is as follows:—
| Silica | 37.46 | Lime | 0.60 |
| Oxide of Copper | 0.44 | Magnesia | Trace |
| Alumina | 4.75 | Arsenious Acid | Trace |
| Oxide of Cobalt | 5.50 | Oxide of Nickel, Sulphur, &c. | Traces |
| Oxide of Manganese | 27.50 | ||
| Oxide of Iron | 1.65 | Moisture | 20.00 |
With the accession of the Ming dynasty (1368), the golden period of Chinese keramics may be said to have commenced. The first sovereign of the dynasty was Hung-wu, who reigned from 1368 to 1399. In the second year of his reign a special factory at Ching-tê-chên was appointed to supply the Court. Its products were named Kuan-yao, or Kuan-tsü. This name—Imperial Ware—was thenceforth applied to several varieties of choice keramic manufactures, which the connoisseur will, of course, be
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