Kaolin Clay in Saprolite Profile
Kaolinite (Al2Si2O5(OH)4) within Weathered Pegmatite/Granite
sedimentary
Category
Organic (Paper And Cellulose)
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Orthoceras Fossil in Limestone
Orthoceras regulare
sedimentary
Banded Iron Formation (BIF)
Banded Iron Formation (BIF)
sedimentary
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary
Barite
Barium Sulfate (BaSO4)
mineral
Petoskey Stone (Fossilized Rugose Coral)
Hexagonaria percarinata (Calcium Carbonate, CaCO3)
sedimentary
Kaolinite (Chalky Clay)
Kaolinite (Al2Si2O5(OH)4)
sedimentary
Petoskey Stone
Hexagonaria percarinata
fossil
Orthoceras Fossil
Orthoceras sp. (Extinct genus of nautiloid cephalopod)
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Chalk (Sedimentary Limestone)
Calcite (CaCO3)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Petoskey Stone
Hexagonaria percarinata
sedimentary
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Slate
Foliated Metamorphic Rock
metamorphic
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Quartz with Mica (Schist/Pegmatite fragment)
Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(OH)2)
igneous/metamorphic
Sandstone (Calcareous or Quartz-rich)
Arenite
sedimentary
Sandstone
Arenite (SiO2 principal)
sedimentary
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 cement)
sedimentary
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Muscovite Mica
Muscovite KAl2(AlSi3O10)(OH)2
mineral
Sandstone
Arenite (primarily Quartz, SiO2)
sedimentary
Pyrite
Iron Disulfide (FeS2)
mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Chalk
CaCO3 (Calcium Carbonate)
sedimentary
Quartz River Cobble
Silicon Dioxide (SiO2)
Mineral (Primary constituent)
Petoskey Stone
Hexagonaria percarinata
fossil
Muscovite
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Pyrite
Iron sulfide (FeS2)
mineral
Polished septarian nodule
Calcite–aragonite–barite septarian concretion, commonly in a claystone or limestone matrix
sedimentary
Polished/tumbled septarian nodule (likely)
Calcite–aragonite–barite septarian concretion; composition varies, commonly calcite (CaCO₃) with clay/mudstone and iron oxides
sedimentary
Polished agate/jasper nodule
Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide impurities
mineral
Tumbled banded metamorphic stone
Likely banded gneiss or migmatitic gneiss; exact identification requires testing
metamorphic
Petoskey Stone (Fossilized Rugose Coral)
Hexagonaria percarinata
fossil
Septarian Nodule
Septarian concretion (composition: Calcium carbonate, Aragonite, and Siderite/Baryte)
sedimentary
Agate Geode Node
Cryptocrystalline Quartz (SiO2)
mineral
Dyed Purple Agate
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Dyed Agate Geode
Silicon Dioxide (SiO2) with artificial pigment
mineral
Fossilized Coral (Petoskey-like or Favosites)
Anthozoa (Fossilized Coral)
sedimentary
Thunderegg (specifically a Jasper/Agate-filled Geode nodule)
Silicon Dioxide (SiO2) within Rhyolitic Matrix
igneous