Alcatraz Penitentiary - SOLD 2.75" Showcase Concrete space in the Bearpaw Formation

in the Bearpaw Formation

our classic acrylic specimen jar size and a large cross section featuring the 1908 growth rings

An individual certificate of authenticity is also included

but this larger specimen measures approximately 1 cm in length

embarking on its maiden voyage on April 4

Alcatraz Penitentiary - SOLD 2.75" Showcase Concrete space in the Bearpaw FormationThis is an authentic piece of concrete from Alcatraz Penitentiary. Yes, an actual piece of The Rock!" This particular specimen measures 2. 75" along the widest point. This specimen, from the famous Alcatraz island, saw some 1,500 prisoners pass by it during the prison's operation. A certificate of authenticity is included.