Copper Ruby Vase’s
Copper belongs to a group of metals known as the Nobel Metals.
Copper ruby glazes were first perfected in china during the Sung Dynasty and have been highly prized in history. This ancient glaze is probably the most difficult colour to achieve in all of ceramics. The Sung Dynasty was a ruling dynasty in China between 960 and 1279 A.D.
During the time of this dynasty, paper banknotes were first produced, gunpowder and the compass were discovered and Chinese arts received great support from the emperor. A major part of the arts was the development of beautiful ceramics – not least of which was the Copper Ruby Glaze.
To achieve this glaze requires an exacting chemical composition as well as a carbon rich flame at just the right temperature.
At this temperature the copper in the glaze will have an available oxygen molecule. The excess carbon in the kiln atmosphere is hungry for oxygen and will rob it from the copper turning it from copper oxide (green in colour) to the metallic form which is red.
The beautiful colour found in glazes containing noble metal crystals is mainly produced by the absorption of light by the metal crystals. Big crystals scatter enough light to make the glaze appear opaque in reflected light and (densely) coloured in transmitted light. We almost always look at, rather than through glazes, so it is the reflected results which matter most to us.
Copper Ruby Vases by Gordon Hutchens of Denman Island, B.C. Canada
No comments:
Post a Comment