I don't think there
is another glaze in the early years of a potter's career that could make
him/her more aware of the greatness of the ceramic art than an exquisite
sample of Jun (Chün) ware like this one in the Asia Society collection.
And any potter who
tries to duplicate this glaze soon realizes how difficult it is to do.
The color is derived
from copper, ceramics most protean mineral but also its most fugitive.
Since these glazes were regional phenomena they are hard to reproduce
elsewhere. Even with our technical ability today to analyze the constituents
of these ancient glazes, they remain elusive.
One thing is obvious,
there must have been a copper deposit in the region of the Jun ware kilns,
as well as other minerals sympathetic to producing copper colors in their
glazes. The intriguing purple and red passages found on Jun ware are splashes
of copper in some form, perhaps a finely ground copper oxide or carbonate,
or a soluble salt of copper. Because copper migrates in a glaze it can
wick through the wall of the body while it is in an absorbent state. This
accounts for the color found inside this bowl as well as the outside-the
copper has migrated through its wall.
How they did these
amazing glazes is a technically fascinating subject. But why they did
it is the mystery of artistic intuition aided by some fortuitous
things like location and some mystical things like genius.