Ironstone Concretion
Ironstone (primarily Siderite or Limonite)
sedimentary
Category
Mineral (Organic)
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Black Shale
Argillaceous Chert/Shale
sedimentary
Jasper
Silicon dioxide (SiO2)
sedimentary
Bivalve Fossil (Internal Mold/Steinkern)
Class Bivalvia (Fossilized Mold)
sedimentary
Polished amber-colored stone, possibly chert or jasper
Uncertain from image; likely microcrystalline quartz (SiO₂) if chert/jasper
mineral
Amber
Succiniferous fossil resin (C10H16O)
mineral
Amber (Copal)
Succinate (Fossilized Resin)
mineraloid
Amber / Copal
Succinite (fossilized tree resin)
mineraloid
Shale with Pyrite
Clastic sedimentary rock containing Iron Disulfide (FeS2)
sedimentary
Weathered River Rock (likely Chert or Basalt with algae)
Silicon dioxide (SiO2) with organic biofilm
sedimentary
Chert / Flint
Silicon Dioxide (SiO2)
sedimentary
Geode (Unopened)
SiO2 (Quartz-filled Sedimentary Nodule)
sedimentary
Jasper
Silicon Dioxide (Microcrystalline Quartz, $SiO_2$)
sedimentary
Siltstone with Fossil Cast
Sedimentary Rock (Siltstone / Fine-grained Sandstone)
sedimentary
Chert Nodule / Ironstone Concretion
Microcrystalline Quartz (SiO2) with Iron Oxides
sedimentary
Gray River Pebble (likely Limestone or Siltstone)
Sedimentary Rock (Calcium Carbonate or Siliciclastic)
sedimentary
Chert (with Epidote/Quartz veining)
Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions
sedimentary
Turquoise and Spiny Oyster (Heishi style beads)
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Spondylus (Spiny Oyster shell)
mineral and organic gemstone
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Fancy Jasper
Jasper (Cryptocrystalline Quartz, SiO2)
sedimentary
Pitted Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossilized Shark Tooth
Chondrichthyes (Class)
fossil
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
sedimentary
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
mineral
Fossilized Coprolite
Coprolite (fossilized feces)
sedimentary
Petrified Wood
Silicified Wood (mainly Quartz / SiO2)
fossil
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Pink Opal
Hydrated silica (SiO2 "n H2O)
mineral
Green Moss Agate
Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)
mineral
Seashell Fragment
Calcium carbonate (CaCO3) - primarily Aragonite or Calcite
fossil
Sandstone (Glauconitic)
Glauconitic Quartz Sandstone (SiO2 + (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Mammoth or Mastodon Tooth Fragment
Mammuthus / Mammut molar fragment
fossil
Fossilized Shark Tooth
Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron
sedimentary
Yellow Jasper
Quartz (Silicon Dioxide, SiO2 with impurities)
sedimentary
Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Bone Fragment
Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)
sedimentary
Chalcedony (Agate / Jasper Specimen)
Silicon Dioxide (SiO2)
mineral
Pyrite in Slate or Shale
Iron Sulfide (FeS2) in Argillaceous Matrix
mineral
Shungite
Shungite (carbon-rich Precambrian rock)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Shungite
Shungite (carbon-rich Precambrian mineraloid)
mineral