White glaze is the natural colored glaze
of the porcelain. Both the common porcelain clay and glaze
material contain more or less iron oxide. Therefore, it will
certainly take on various shades of cyan after the ware is
fired. But it will be white glaze if the iron element content
of the glaze material is less than 0.75%. White color agent
is not put in the glaze material during the process of manufacturing
ceramic white ware in ancient times. On the contrary, the
porcelain clay containing less iron element and glaze material
are used to manufacture all together so that the iron content
is reduced to the lowest level. Then pure transparent glaze
is coated on the pure white porcelain body. At last, the ceramic
whiteware is fired in this way.
The white glaze emerges in the North Dynasty. The ceramic
whiteware excavated from the grave of Fan Cui in the period
of Beiqi is the earliest ceramic whiteware found in our country
up to now.
Lovely white glaze
| Sweet white is a kind of white glaze
first fired at Yongle kiln. Most of ceramic white ware products
made in Yongle can be seen their shadows by sunshine because
they are as thin as semi-body. White glaze is coated on the
surface of the egg shell wares carving secret decorative pattern.
It will give you a feeling of sweet. Therefore, it is called
"sweet white". Because the lovely white glaze is fired
successfully at Jingdezhen, it creates favorable conditions
for the development of decorative porcelain in the Ming Dynasty.
The "doucai", "wucai" and famille rose in
the Ming and the Qing Dynasty cannot show their bright colors
until the ceramic whiteware gains great achievements.
The lovely white glaze is still fired in the Qing
Dynasty. The lovely white glaze made during the Qing Dynasty is
also called creamy white because its color and lustre is white,
bright and smooth just like powered milk and no crackles.
| "qingbai" glaze is also
called bluish white. It was first created in Jingdezhen kiln
at the early days and the middle period of Beisong. The color
of the glaze is suffused with cyan in white because of the low
iron content of the "qingbai" glaze. Both the inside
and the outside of the design carved secretly on the ware can
be seen because the cover coat is thin, bright and clean. Additionally,
it is fired extremely thin. It is almost white except a little
nattierblue on the edge of the design. Therefore, it is called
"qingbai" glaze. It is also called shadowy blue, "yinqing"or
"zhaoqing" by some people.
The output of the bluish white porcelain increases
sharply during the rule of Nangsong because the way of upside down
firing is adopted. Therefore, it forms a "qingbai" resource
series in the southern part of our country around Jingdezhen. There
are also some kilns firing the bluish white porcelain in Anhui,
Fujian, Hubei and other places besides Jingdezhen. From the Yuan
Dynasty, the "qingbai" glaze shows cyan slightly. It is
not clearer, brighter than the "qingbai" glaze in the
Ivory white, namely the pure white glaze made in Dehua
kiln in the Ming Dynasty. The color of the glaze is extremely pure
because the ferric oxide content of the glaze is too low and the
potassium oxide is not extremely high. Additionally, it is fired
by neutral atmosphere. Seeing from the outward appearance, the colour
and lustre is smooth, bright and milky white just like congealed
flat. It shows pink or milky white faintly in the glaze by the sunshine.
Therefore, it is called ivory white or lard white. The color of
the glaze is also called goose down white or Chinese white by European.