Brachiopods
Learn to recognize brachiopod shells and molds, separate them from bivalves, and interpret their marine context without assuming that possession or collection is legal.
Open the guideRead the fossil. Respect the place.
Fossil identification and legal collecting
Use visible anatomy, preservation, rock context, and honest uncertainty to recognize common nonvertebrate and plant fossils. Before touching or moving anything, identify the land manager and check the current rule for that exact place.
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A fossil name never proves collection is legal
Rules depend on ownership, managing agency, closures, scientific significance, quantity, tools, and intended use. National parks prohibit recreational fossil collecting. Some other federal lands allow limited casual collection of certain common invertebrate and plant fossils, but local restrictions still apply.
Read the U.S. collecting-law guideEight field guides
Identify the structure—not just the silhouette
Each guide begins with observable features, then checks lookalikes, preservation, geologic meaning, identification limits, and legal handling.
Bivalves
Identify fossil clams, oysters, mussels, and related bivalves using hinge, valve, ornament, and preservation clues while keeping taxonomic and legal limits explicit.
Open the guideGastropods
Recognize fossil snails from their whorled single shells, distinguish common lookalikes, and understand what preservation and context can—and cannot—show.
Open the guideTrilobites
Use the three-lobed body plan, segmentation, head, thorax, and tail to assess possible trilobite fossils without mistaking simple ridges or fragments for a complete animal.
Open the guideCrinoids
Recognize common crinoid stem pieces and rarer body parts, distinguish circular lookalikes, and interpret their marine limestone context cautiously.
Open the guideBryozoans
Recognize fossil bryozoan colonies from their repeated microscopic openings and growth forms, while separating them cautiously from corals and patterned rock.
Open the guideCorals
Identify major coral fossil patterns from corallites, radial partitions, colony form, and geologic context without treating every porous limestone as coral.
Open the guidePlant fossils
Recognize leaves, stems, and petrified wood using biological structure and preservation clues while avoiding manganese dendrites, banded silica, and other common lookalikes.
Open the guideA responsible sequence
Observe, document, verify, then decide
Formation and state context can help test an identification. Compare the observation with the U.S. formation library and state geology guides, but never treat a map or fossil record as proof of access or permission.
- Observe in place. Photograph multiple angles with scale, but avoid exposing a precise sensitive location publicly.
- Describe structure. Record symmetry, repeated parts, surface ornament, matrix, and preservation before choosing a name.
- Compare several possibilities. Treat fragmentary evidence as provisional and stop at the taxonomic level the anatomy supports.
- Verify land status and rules. Ask the responsible land manager when ownership, boundaries, significance, or allowed methods are uncertain.
- Leave and report unusual finds. Do not excavate or disclose a sensitive coordinate; document it and contact the land manager or qualified paleontologist.