A very RICH and unusually large specimen of montroydite, a rare Terlingua mercury mineral! The piece has a thick vein running through it, and is rich with microcrystals on attractive contrasting calcite. The dark red is the montroydite and the orange mineral is kleinite. Edgar Bailey was a noted mineralogist and field collector of Terlingua minerals, and the species Edgarbaileyite is named after him in honor. This is from his collection and was self-collected by him, part of a suite of such pieces (not from Feinglos coll.)