Tell me about ceramics?

There were in the past some arguments that copper was first smelt by accident also in campfires, but that seems improbable as campfires are about 200°C short of the temperature needed to smelt copper. A more probable path may have been through pottery kilns, invented in Iran by 6000BC. Pottery kilns produce ceramics that can be glazed with colorful earths (mostly metalic oxides) to produce colorful vases; it happens that malachite (copper oxide) is a colorful green stone, so a potter that encrusts malachite in a ceramic vase in a coal-fired kiln will produce a few droplets of metallic copper (ruining his vase). That may have set the way to smelt copper.