Rough Agate/Chert Nodules
Cryptocrystalline Quartz (SiO2)
sedimentary
Category
Sedimentary Or Igneous (Host Environment)
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Fenestella Bryozoan Fossil
Fenestella (class Stenolaemata)
fossil
Yellow-brown chert or jasper
Microcrystalline quartz (SiO₂), likely iron-oxide-bearing chert/jasper
sedimentary
Granitoid Gneiss with Feldspar Vein
Gneiss (High-grade Metamorphic Rock) with Potassium Feldspar (KAlSi3O8)
metamorphic
Weathered rock fragment (likely granite or quartz-rich sandstone)
Uncertain; possible granitic fragment containing quartz and feldspar
igneous
Chert (Jasper-like Silicate)
Microcrystalline Quartz (SiO2)
sedimentary
Pyritic Gneiss
Metamorphic Gneiss with Pyrite inclusions
metamorphic
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Crystalline Silica (SiO2)
sedimentary
Wishing Stone (Basalt/Siltstone with Quartz/Calcite vein)
Carbonaceous Siltstone with Quartz (SiO2) or Calcite (CaCO3) vein
sedimentary
Botryoidal Pyrite
Iron Sulfide (FeS2)
mineral
Milky Quartz on Matrix
Quartz (Silicon Dioxide, SiO2)
mineral
Banded Gneiss
Gneiss
metamorphic
Quartz (Pegmatitic Quartz with Feldspar)
SiO2 (Silicon Dioxide)
mineral
Chert in Limestone (or Flint Nodule)
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Cannonball Concretion
Calcite-cemented Sandstone Concretion
sedimentary
Pyrite-rich rock (likely pyrite-bearing schist)
Pyrite (FeS₂) in a foliated metamorphic matrix; exact host rock cannot be confirmed from the image
metamorphic
Sandstone (with Lichen)
Arenite (composed primarily of SiO2)
sedimentary
Garnet-bearing gneiss
Biotite–garnet gneiss, typically quartz + feldspar + biotite + almandine garnet
metamorphic
Weathered iron-rich rock, possibly basalt or limonite-bearing sandstone
Undetermined; likely Fe-oxide-stained basalt or ferruginous sandstone (hematite/goethite-bearing)
igneous
Quartz Veinated Sandstone or Siltstone
Silicon Dioxide (SiO2) within a clastic sedimentary matrix
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Citrine (Heat-treated Amethyst)
Silicon Dioxide (SiO2) with iron impurities
mineral
Mica-bearing metamorphic rock, likely schist
Muscovite/biotite mica schist with quartz and feldspar
metamorphic
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) in matrix
mineral
Pyrite (on host rock/ore)
Iron Sulfide (FeS2)
mineral
Milky quartz vein fragment
Quartz (silicon dioxide, SiO₂), massive or granular variety
mineral
Pyrite in Host Rock
Iron Disulfide (FeS2)
mineral
Likely weathered metamorphic rock (possibly schist or gneiss)
Indeterminate; probable mica-rich quartz–feldspar metamorphic rock
metamorphic
Banded Gneiss Pebble
Gneiss (Metamorphic Rock)
metamorphic
Milky Quartz with Hematite/Limonite staining
Silicon Dioxide (SiO2)
mineral
Likely rose quartz
Quartz (SiO₂), variety rose quartz
mineral
Rough Ruby
Corundum (Al2O3 with Chromium impurities)
mineral
Muscovite Mica
Muscovite / KAl2(AlSi3O10)(OH)2
mineral
Quartz (Specifically Clear to Smoky Quartz point)
Silicon Dioxide (SiO2)
mineral
Quartz Vein / Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within metamorphic/igneous matrix
igneous/metamorphic
Banded Gneiss / Metamorphic River Pebble
Gneiss (Foliated Metamorphic Rock)
metamorphic
Turquoise
Hydrated phosphate of copper and aluminum - CuAl6(PO4)4(OH)8·4H2O
mineral