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Toothhound

Geological curios

Mineral curios — pyrite, amber, agates, concretions — that ride along in the same gravel as the fossils.

Detailed entries

Amber droplets
Tiny droplets and chips of fossil tree resin from the Raritan Formation occasionally wash into Big Brook and a few other NJ creeks. Many contain microscopic insects. Genuine NJ amber is rare enough that most people hunt a lifetime without finding a piece — bag it carefully.
Pyrite (fool's gold)
Bright brassy cubes and clusters that fooled prospectors for centuries. In creek gravel it forms when iron-rich groundwater meets the sulfur left behind by decaying organic matter — which is why pyrite often replaces fossils, preserving belemnites and shells in metallic gold.

Also reported in this category

These show up on location dossiers but don't have a dedicated guide entry yet. Each links to the first site where it's reported.

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