An enamel made of special porcelain used in jewelry as insignia and art objects.
See Alexandrite Tsarstone collectors guide, Definition of Jewel enamel, http://w.alexandrite.com/viewpage.html?id=GG-095-00002 (An enamel made of special porcelain used in jewelry as insignia and art objects.) (as of May. 31, 2026, 19:33 GMT).