This piece displays a cascade of graded Acanthite crystals. Fresnillo is a humongous Carbonate Replacement Deposit probably best known by collectors for its hoppered and skeletal style Acanthite specimens. Acanthite is one of the main silver ore minerals. The skeletal and hopper style of Acanthite terminate as sharp, well-defined cubic crystals. Specimens like this from the Proano Mine are regularly labeled as pseudomorphs after Argentite; however, the two silver sulfide minerals are paramorphs. Therefore, depending on the temperature and pressure conditions, either would be the stable mineral. At surface conditions, only Acanthite is stable. The piece is complete all the way around and elegantly displays on a custom acrylic base.