William W. Jefferis (1820-1906) was a prominent Pennsylvania mineral collector and businessman who was one of the leading collectors of the 19th century. He lived in Chester County, Pennsylvania (outside Philadelphia), and worked in banking and finance, eventually ending up in senior leadership positions which afforded him the discretionary income to pursue his mineral collecting passion and acquire some of the finest specimens available during his time period. By 1900, Jefferis was thinking of selling his enormous collection, and numerous important collectors and museums expressed interest. In 1904 Andrew Carnegie purchased Jefferis' entire collection of over 14,000 specimens and in January of 1905 donated it to the Carnegie Museum of Natural History. Two railroad boxcars were needed to transport the collection to Pittsburgh. William, Jefferis died in New York on February 23, 1906.
The following specimens were de-accessioned from the Carnegie Museum of Natural History in the 1990's, and we are happy to be able to offer them here. They retain Jefferis' original labels, and offer a fascinating snapshot at some of the important localities and minerals of the mid to late 19th century. Enjoy!