This is an important crystal of the species for the sheer size and thickness! The luster is spectacular. It is, on first glance, hard to place for being a pyrargyrite because it is so robust a crystal. From the important locality of Fresnillo, this is an outstanding compound crystal with a brilliant, metallic luster. The termination is very good, and there is minor matrix. One incipient crack is near the bottom, but that is not cracked through or repaired. Despite the thickness of the crystal, there is still light transmission and a red glow when brightly lit. But just under normal lights, it is so bright and shiny that you think it must be a sulfide of some kind, rather than Pyrargyrite at the top of its game for luster.