dufrenoysiteMin.|djuːfrɪˈnɔɪzaɪt| [Named 1845 after M. Dufrénoy: see prec.] An arsenical sulphuret of lead, occurring in highly modified prisms, of grey colour and metallic lustre. 1848Amer.Jrnl.Sc.Ser. ii. V. 268 Dufrenoysite is an arsenical sulphuret of lead.1868Dana Min. 92.