This piece is from the Nacimiento Mine in San Pablo, Sandoval County, New Mexico, USA. This was an open pit mined that was operated for the recovery of copper minerals and ores found in the remains of fossilized wood logs from the Triassic Period. Six different minerals were identified as coming from the mine including chalcocite, a copper sulfide containing the elements (Cu, S), and malachite (Cu,C, O, H) a carbonate. This piece consists of a combination of the two. It measures 2 1/2 x 1 5/8 x 3/4 inches or 64 x 41 x 19 mm.