ceresin / sericin [ˈsirəsɪn]
ceresin – n. – (also ceresine) a white or yellow hard brittle wax made by purifying ozokerite and used a substitute for beeswax; also a petroleum wax having similar physical properties
sericin – n. – a gelatinous protein that cements the two fibrin filaments in a silk fibre and that can be removed by degumming; called also silk gum