Chert (Flint Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
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Chert (Nodule)
Chert (variety of microcrystalline quartz, SiO2)
sedimentary
Green Jasper / Plasma
Microcrystalline Quartz (Chalcedony), SiO2 with inclusions
gemstone
Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
Weathered granite or granitic gneiss
Granite: quartz, feldspar, and mica; possibly weakly foliated gneiss
igneous
Shark Tooth Fossil
Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)
fossil
Fossil Coral
Rugosa or Tabulata coral fossil (Calcite/Silica replacement)
fossil
Sandstone
Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)
Sedimentary Rock
Slate
Slate (Low-grade regional metamorphic rock)
metamorphic
Slate
Slate (Low-grade foliated metamorphic rock)
metamorphic
Chert (Yellow Jasper/Flint)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
sedimentary
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Quartzite
Silicon Dioxide (SiO2)
metamorphic
Shale
Fissile Mudstone (primarily composed of clay minerals and quartz)
sedimentary
Petrified Wood
Silicified wood (Quartz replacement of organic wood structure)
fossil
Basalt
Extrusive mafic igneous rock
igneous
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Basalt
Basalt (Mafic volcanic rock)
igneous
Biotite-bearing granite or gneiss
Felsic granitoid; chiefly quartz, feldspar, and biotite mica
igneous
Quartz Breccia with Iron Staining
Tectonic or Sedimentary Breccia (SiO2 with Fe2O3)
sedimentary
Diorite
Plutonic Igneous Rock (NaAlSi3O8, CaAl2Si2O8)
igneous
Charoite
Charoite (Complex silicate mineral rock)
metamorphic
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Diorite
Diorite (intermediate intrusive igneous rock)
igneous
Limestone
Sedimentary rock composed primarily of Calcium Carbonate (CaCO3)
sedimentary
Fossilized Oyster Shell
Exogyra or Ostrea (Gryphaeidae/Ostreidae family)
fossil
Weathered quartz-rich granitoid (likely granite or granodiorite)
Granite–granodiorite; chiefly quartz (SiO₂), feldspar, and minor mica/amphibole
igneous
Sandstone (with Iron Staining)
Arenite (Silicon Dioxide, SiO2, often with iron oxides like Limonite)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
Greenstone
Metamorphic mafic rock (chlorite-actinolite-epidote schist)
metamorphic
Petrified Wood
Silicified wood (primarily quartz, SiO2)
fossil
Polished red gemstone pendant, likely red jasper or brecciated jasper
Jasper: microcrystalline quartz (SiO₂), commonly with hematite or iron-oxide inclusions
metamorphic
Chert / Pink Chert
Silicon Dioxide (SiO2)
sedimentary
Weathered iron-rich rock, possibly limonite-bearing sandstone or laterite
Limonite/goethite-rich ferruginous rock; exact identification requires testing
sedimentary
Fossilized cylindrical shell or bone fragment
Indeterminate biogenic carbonate or phosphatic fossil; possible fragment of a tubular shell (e.g., scaphopod) or hollow bone
fossil
Chert (potentially Fossiliferous or Jasperoid)
Microcrystalline Quartz (SiO2)
sedimentary
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Serpentine (Serpentinite)
Serpentinite (complex silicate group including lizardite, chrysotile, and antigorite)
metamorphic
Tumbled quartz pebble
Quartz (SiO₂), likely milky or fractured rock crystal
mineral
Schist (Greenschist / Mica Schist)
Foliated Metamorphic Rock (rich in chlorite, muscovite, and quartz)
metamorphic
Limestone
Sedimentary rock composed mainly of calcite (CaCO3)
sedimentary
Granitoid (Granitic Rock)
Granitoid (Quartzo-feldspathic plutonic rock)
igneous