DELAWARE
State Mineral: Sillimanite (1977)
State Fossil: Belemnite (1996)
Delaware is referenced as The Diamond State but don’t be dreaming about hitting it big. Unfortunately, no diamonds are to be found in Delaware. Instead you can try your hand at finding many of its other minerals, fossils, and petrified wood.
Garnet and Sillimanite can be found in Delaware. The following Fossils can also be found.
Belamnite Fossils (the State Fossil)
Miocene Fossils. One of the richest sites for Miocene Fossils is the Pollack Farm Site.
Pleistocene Epoch. Near Dagsboro you can find younger fossils from the Pleistocene Epoch.
Disclaimer
Please note that rock collecting locations are always changing so be sure to check with the site owner for the most current information before going.
Dig safe, never go underground, and make sure to get permission from the landowner to search for and collect rocks.