protoporcelain
/ˌprəʊtə(ʊ)ˈpɔːs(ə)lɪn/ /ˌprəʊtə(ʊ)ˈpɔːs(ə)leɪn/noun
A type of early stoneware with a feldspathic glaze, closely resembling true porcelain but lacking its translucent qualities; especially a ceramic ware produced in ancient China under the Han dynasty (206 b.c.– a.d. 220). Also as a count noun: an item made of this.
Origin
Early 20th century. From proto- + porcelain.