ForMatter/Finishes/glaze/Celadon glaze
finish_glaze_celadon

Celadon glaze

glaze · translucent · celadon, qingci, Goryeo celadon, Longquan celadon

A translucent gray-green glaze fired in reduction — the iron in the glaze loses an oxygen and turns from rust-tan to soft jade. Song-dynasty Chinese tea bowls, Goryeo Korean inlay-celadon, Longquan kilns. Reads cool, watery, ancient. Crackle is part of the design, not a defect.

Feldspathic glaze with 1–3% iron oxide as colorant, fired to cone 9–10 (~1280 °C) in a reduction atmosphere — kiln starves of oxygen so the iron is held as Fe²⁺ (gives green) rather than Fe³⁺ (rust). Glaze chemistry is high-feldspar / high-silica / low-flux for a stiff, translucent layer that pools in carved relief and breaks into a soft fishnet crackle on cool-down. Typical thickness 0.6–1.2 mm. Modern studio celadon often skips the reduction by mixing in a small fraction of titanium or chrome to fake the green; the glassy depth differs.

character — translucent jade green-gray, watery glaze pool, fishnet crackle, ancient register.

Finish properties

  • leveltranslucent
  • subcategoryiron-reduced feldspathic
  • applies toceramic

Second life

reversibilityzero — fired ceramic glaze cannot be unfired; the glassy layer is permanent. Damaged or chipped glaze can be re-glazed and re-fired with chemistry-compatibility planning.
blocks substrate recyclingno
renewabilitymoderate — re-glazing and re-firing is a studio-renewability path for damaged ceramic; the constraint is the original-firing temperature (the re-glaze must fire below the original).

Robin Hopper *The Ceramic Spectrum* (Krause, 2nd ed.); Daniel Rhodes *Clay and Glazes for the Potter*.