English: Deep Dish, Spain
After 1475 Tin-glazed earthenware with lustred decoration V&A Museum no. 1680-1855

Source: http://www.vam.ac.uk/images/image/33766-popup.html

via Wikipedia:

“Lusterware or Lustreware (respectively the US and all other English spellings) is a type of pottery or porcelain with a metallic glaze that gives the effect of iridescence, produced by metallic oxides in an overglaze finish, which is given a second firing at a lower temperature in a “muffle kiln“, reduction kiln, which excludes oxygen.”

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