If you are looking for fossils in the state of Pennsylvania, Common Fossils of Pennsylvania is a good guide to start with. It was written by Donald M. Hoskins for the Pennsylvania Geological Survey. This is the fourth series of this publication. You can download a digital copy using the link below. You can also order a physical version by contacting the PA Geological Survey by email via a link on the DCNR Geology Publications and Data page.
I have found several of the common fossils showcased in the book locally. However, Pennsylvania differs greatly in geologic age and you’ll find different fossil families in different geographic locations. For example, central Pennsylvania is a much better place to find medium to large-sized Trilobites, a favorite among fossil collectors.
General PA Geology Publications
A large list of publications is available by visiting this link. These include several historical publications describing all sorts of aspects of Pennsylvania’s geologic features.
Other Pennsylvania Fossil Publications
This is an earlier, more comprehensive publication that also included a county-by-county guide with a collection location. However, several of these were not on public lands and required permission to visit. After many attempts by individuals to collect without permission, this booklet was no longer published. It is also becoming dated, with several locations now being off-limits, destroyed, or otherwise not worth the trip.
For example, the location in Westmoreland County was at the interchange of PA 22 and PA 66. This interchange has been completely rebuilt since the material was written, with the original site not available. The location in Allegheny County is closed due to dangerous rockfalls. A site in Indiana County is now only open to students at Indiana University. The location in Armstrong County, the county where Parks Township is located, has now eroded greatly, covering any easy access to fossils that were available.
Others State Publications but Useful Here
Several other states have publications that are useful in Pennsylvanian. New Mexico, Arizona, Kansas, Texas, Illinois, Kansas, Nebraska, Iowa, Ohio, Kentucky, and West Virginia all have relatable stratum that correlates with stratum locally. The same floods that brought ancient seas to Western Pennsylvania also flooded the land with water in these places. While the Brush Creek limestone locally is only a foot or two thick, so places have it tens of feet thick from the same time period.
Ohio Department of Natural Resources – Fossil Species Search
A useful search for different fossil species available in Ohio.
Ohio Publications of Interest
Ohio is very close to Western Pennsylvania and has published a far greater amount of content on fossils than Pennsylvania has. There are several guides available that are excellent resources for the identification of fossil specimens. You can email them, however, you must either call to give payment information, or mail them a physical form. The number to call is (614) 265-6576 during their business hours. The In-Print books can be found online on various marketplaces for sale, but they are typically double to triple in price. As of June 2021, Bulletin 70 was $30 and Bulletin 71 was $20.
The Ohio geology publication database can be searched online.
- Ohio Trilobites
- Fossil Collecting in Ohio
- In Print – Bulletin 70: Fossils of Ohio – A very large, comprehensive guide to Ohio fossils. A must-have if you are collecting in similar fossil systems.
The following publications are excellent for Pennsylvanian Fossils
- In Print – Bulletin 71: Pennsylvanian cephalopods of Ohio – Excellent guide to Pennsylvanian period Cephalopods. Very relevant to finds in Western Pennsylvania.
- In-Print or Download – Pennsylvanian trilobites of Ohio (Report of Investigations 142)
- In-Print or Download – Pennsylvanian marine Bivalvia and Rostroconchia of Ohio (Bulletin 67)
- Download – Pennsylvanian Brachiopods (Bulletin 63)
- In-Print or Download – Pennsylvanian conodont localities in northeastern Ohio (Guidebook 3)
Illinois and Arizona, two localities that have excellent Carboniferous rocks exposed for collecting
- Illinois State Geological Survey – Common Types of Illinois Fossils
- H. Wesley Peirce, 1981, The Mississippian and Pennsylvanian (Carboniferous) Systems in the United States – Arizona