Home / Explore / Minerals / Geffroyite Minerals Geffroyite geffroyite (Cu,Fe,Ag)9(Se,S)8 Geffroyite Mineral Specimen For Sale — via www.dakotamatrix.com · Source Overview Geffroyite is a mineral species (sulfide mineral). It crystallises in the cubic system. Nickel–Strunz class: 2.BB.15. Scientific references Geffroyite — Wikidata. https://www.wikidata.org/wiki/Q3759213 Link
