What is a case or holder made of fire clay, in which fine pottery is inclosed while baking in the kin. [Written also saggar, sagger, and segger.] Ure called?

seggar — A case or holder made of fire clay, in which fine pottery is inclosed while baking in the kin. [Written also saggar, sagger, and segger.] Ure. (Webster's 1913.)

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