This sample of Babingtonite is displayed in the Smithsonian Museum of Natural History. Babingtonite is a silicate mineral which contains five of the "big 8" elements. Its composition is Ca2(Fe,Mn)FeSi5O14(OH). The sample is about 15x16 cm and is from Mount Tom, Holyoke, Massachusetts. It is described as Babingtonite with prehnite and calcite. The color of Babingtonite is typically dark greenish-black.
Named after Dr. William Babington (21 May 1756 - 29 April 1833), Irish physician and mineralogist, founding member and President (from 1822 to 1824) of the Geological Society of London.