Stock Photo - Three dated fragments Werra pottery, sludge technique and sgraffito, dish plate bowl crockery holder soil find ceramics earthenware clay engobe glaze lead glaze, hand-turned glazed petite sgraffito baked Fragments of dated Werra earthenware. Red shard Decorated in sludge technology ring-seal technique and sgraffito. White engobe green accents obtained by application of copper oxide On fragment deer or sheep can be depicted fragment, 16 ** archeology Rotterdam City center Stadsdriehoek Schielandshuis decorate serve serve food Soil discovery: Schielandshuis during the restoration.