Rounded gray river pebble, likely fine-grained sandstone or siltstone
Indeterminate clastic sedimentary rock; possibly quartz-rich sandstone or siltstone
sedimentary
Category
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Goldstone and pink quartz bead strands
Goldstone is aventurescent copper-bearing glass; pink beads are likely rose quartz (SiO₂), though dyed or glass imitations are possible
mineral
Diamond
Diamond (pure carbon C)
mineral
Blue topaz (likely treated)
Topaz, Al₂SiO₄(F,OH)₂
gemstone
Granite River Stone
Phaneritic Felsic Igneous Rock
igneous
Limestone (Weathered)
Sedimentary carbonate rock, primarily calcium carbonate (CaCO3)
sedimentary
Quartz
SiO₂ (Silicon Dioxide)
Mineral
Quartzite
Metamorphic Quartz Rock (SiO2)
metamorphic
Black Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Fossilized shell fragment
Indeterminate fossil mollusk; likely a silicified or mineral-replaced bivalve/gastropod fragment
fossil
Red Quartzite
Quartzite (Metamorphosed Quartz Arenite)
metamorphic
Gabbro
Phaneritic Basic Igneous Rock (Gabbro)
igneous
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Shale with Coprolite influence
Argillaceous sedimentary rock (Shale/Mudstone)
sedimentary
Orbicular Jasper
Silicon Dioxide (SiO2)
sedimentary
Travertine (Ceramic Tile)
Terrestrial Sedimentary Rock / Calcium Carbonate (CaCO3)
sedimentary
Herkimer Diamond
Quartz (Silicon Dioxide - SiO2)
mineral
Greenstone / Serpentinite
Serpentinite (complex of Mg, Fe, Ni, Al, Zn, Mn silicate minerals including Antigorite, Lizardite, and Chrysotile)
metamorphic
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
metamorphic
Jasper
Silicon Dioxide (SiO2)
sedimentary/mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Tumbled carnelian
Carnelian, orange-red chalcedony (microcrystalline quartz, SiO₂)
gemstone
Tumbled amethyst
Quartz, crystalline silicon dioxide (SiO₂), purple variety colored mainly by iron impurities and irradiation
gemstone
Rough Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Quartzite
Metamorphic Quartzite (primarily SiO2)
metamorphic
Dragon Vein Agate (Dyed)
SiO2
mineral
Quartzite
Metamorphic Quartzite (primarily SiO2)
metamorphic
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Sandstone
Arenite
sedimentary
Jasper (likely Iron-stained)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Copper
Native Copper (Cu)
mineral
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Coal (Bituminous Coal)
Caustobiolith / Sedimentary Rock
sedimentary
Gravelly, weathered sediment (likely glacial till)
Unconsolidated diamicton; mixed lithologies, commonly including quartz, feldspar, and weathered silicate rock fragments
sedimentary
Jasper
Silicon dioxide (SiO2)
sedimentary
Likely weathered iron-rich stone
Uncertain; possibly limonite/goethite-bearing rock
mineral
Iron-stained quartzite or quartz-rich sandstone
Quartzite, predominantly SiO₂, with iron-oxide staining
metamorphic
Basaltic volcanic pebble
Fine-grained mafic igneous rock, chiefly plagioclase and pyroxene, commonly with olivine and iron-titanium oxides
igneous
Tumbled citrine quartz (likely heat-treated amethyst)
Quartz, SiO₂; crystalline variety citrine
mineral
Quartzite
Quartzite (mostly SiO2)
metamorphic
Green Banded Agate
Agate (Variety of Chalcedony/Quartz), SiO2
mineral
Likely petrified wood or silicified fossil fragment
Silicified wood; predominantly microcrystalline quartz (SiO₂)
fossil