This is a rare tetrahedrite from China, from a new find apparently. It has sharp, textbook crystals to over an inch, some coated on oriented faces by incredibly metallic, bright chalcopyrite in a micro-thin layer. It looks like the tetrahedrite crystals were dipped in gold plate, on those faces. Small calcites are also attached for texture. The piece is nearly complete all around, with just a small contact area on bottom. Although a fine specimen in its own right, I bought this in part because it was a freak piece, to my eyes, just a single nice specimen from "a new mine" in the rich Nan Dan area where so many calcites have come from. Time will tell whether more come, or none...