Finding fossils is pretty much guaranteed at this off-the-beaten-track park about 70 miles from Philly, in the heart of New Jersey.
During the Cretaceous Period (about 145-66 million years ago), this part of New Jersey (in fact, much of North America) was covered by a shallow sea teaming with marine life. Today, Big Brook (actually the brook is fairly small!) cuts through these sediments, exposing the fossilized remains of these marine (and occasionally terrestrial) species.
Collecting is easy and straightforward. You can use a kitchen colander, but a sifter box is pretty easy to make with chicken wire and scrap lumber. Basically, all you do is put a couple shovel fulls of gravel in the box (walk along the stream to find areas of exposed gravel), swish it in the water to remove to dirt, then examine closely. Fossilized squid remains, fossil mollusk shells, and fossil shark’s teeth are all very common.
Two hours of casual walking and sifting netted Tobey and I this collection of shark’s teeth:
Collecting rules are pretty simple: small hand trowels or shovels only, digging in the stream area only (not the banks), 1 small ziplock bag of treasures per person.
Access from the pull-offs along Boundary Road. You can head either way along the trail that parallels the stream. At last visit (Sept. 2020) there was a port-a-potty set up here. Other than that, the nearest facilities, restaurants, etc. are in Freehold, about 15 minutes away.
For more details and an ID guide: