The collections are an invaluable repository of rock, mineral and meteorite specimens that are available for study by scientists or exhibited by educational institutions. Over 200,000 samples are maintained by the department, and the number is continually increasing as new acquisitions are made. The specimens often represent localities of particular scientific significance, sites that are not generally accessible, or represent a one-of-a-kind specimens such as meteorites, gems, and drill core.
The meteorite collection goes back to the earliest history of the Museum. The first meteorite in the collection was a 46g piece of the Searsmont (H5 ordinary chondrite) donated in 1872 by Mr. G.M. Brainerd of Rockville, Maine.
Minerals and gems have been part of the Museum since it opened in 1869. The AMNH purchased its first major mineral collection in 1874 from S.C.H. Bailey, a New York lawyer.
The American Museum is home to a collection of approximately 5,000 samples representing important mineral deposits from around the world. These deposits have concentrations of various minerals that are important resources for human consumption.
The Petrology collection consists of several thousand hand samples and a number of drill cores from around the world. This collection is primarily used for research and parts of it are available for loan to researchers outside the museum.