Page 186 - Oriental Series Japan and China, Brinkly

CHINA

Generally the matter used for painting blue porcelain is

cobaltiferous manganese. It is found at no great distance

below the surface of the ground, the excavators not being
obliged to dig to a depth of more than one metre at most.

It occurs in all the provinces of the empire and there are

three grades of it. Before use it has to be baked to red

heat in a mass of clay. From each pound of mineral thus

treated, barely seven ounces are obtained. Blue of the first

quality is always used for the decoration of very fine porce-

lains, or on pieces destined for the palace, with dragon and

phoenix designs. Thus 36 dollars must be spent to obtain

thirteen litres of first-class blue one-half of that sum for a
;

similar quantity of second-class mineral, and one-seventh of

it for the third-class variety. All the best blue used at

Ching-te-chen is found in the province of Che-kiang.

That found elsewhere is inferior. After the mineral has

been roasted it is ground very fine in a mortar of unglazed

porcelain, and afterwards moistened with water. When

painted on the surface of the ware it is black, but becomes
blue by exposure to the heat of the furnace.

It will be observed that in these extracts no men-

tion is made of the Hui-ching, or Mohammedan blue.

This choice mineral ceased, apparently, to be procur-

able after the Chia-ching era (15221566). The

Kang-hsi potters and their successors used the native

mineral only, but used it in such a manner as to

obtain a colour little, if at all, inferior to that of the

choicest Ming specimens. Many other details on the

subject of cobalt are given in the Tao-lu but they
y

embody little information and are grouped in a con-
fused manner. The substance of what they convey

is that blue of the choicest quality was scarce, expen-

sive, and difficult to prepare. Even when the best

mineral was employed, any slight excess of tempera-

ture in -the porcelain kiln sufficed to burn out its tint.
There was, however, a particular variety capable of

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