Flint
SiO2 (Cryptocrystalline Quartz)
Category
Browse sedimentary (with some aspects of mineral replacement) specimens identified by the Rock Identifier community.
Flint
SiO2 (Cryptocrystalline Quartz)
Chert
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (Metamorphic Rock)
Chalcedony (Common Agate)
Silicon Dioxide (SiO₂)
Banded Gneiss with Quartz Vein
Foliated Metamorphic Rock (Gneiss)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
Satin Spar Selenite
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Limonite Concretion
Goethite/Limonite (FeO(OH)·nH2O)
Fossilized Shark Tooth (Otodus obliquus)
Otodus obliquus (Mineral composition: Bio-apatite/Calcium Phosphate replaced by various minerals)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Black Shale
Argillaceous Chert/Shale
Gneiss
Gneiss
Ferruginous Sandstone
Sandstone with Iron Oxide (Limonite/Goethite)
Chert (Black Chert or Flint)
Silicon Dioxide (SiO2)
Rhodochrosite
Manganese Carbonate (MnCO3)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Halite
Halite (Sodium Chloride, NaCl)
Gneiss (Cobble)
Gneiss
Quartz Geode
Silicon Dioxide (SiO2)
Celestite
Celestine (SrSO4)
Concretion
Septarian concretion (likely containing Calcite or Siderite)
Gneiss (with Quartzite layers)
Gneissic Metamorphic Rock
Petrified Wood
Silicified Wood (SiO2)
Flint
Microcrystalline quartz (SiO2)
Flint
Silicon dioxide (SiO2) microcrystalline quartz
Moqui Marble (Moqui Ball)
Ironstone Concretion (Goethite/Hematite cemented Sandstone)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Flint / Chert
Microcrystalline quartz (SiO2)
Chert (Chalcedony/Agate Pebble)
Cryptocrystalline Silica (SiO2)
Red Jasper Pebble
Opaque microcrystalline Quartz (SiO2) with Iron Oxide
Flint (Chert)
Cryptocrystalline Quartz (SiO2)
Flint (Chert)
Cryptocrystalline Silica (SiO2)
Gneiss (foliated metamorphic rock)
Gneiss
Jasper with Quartz Vein
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Ammonite Fossil
Ammonoidea
Quartz Geode
Crystalline Quartz (SiO2) within a sedimentary or volcanic host
Pyrite
Pyrite (Iron Disulfide), FeS2
Sandstone
Arenite (SiO2 based)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (Metamorphic Rock)
Lepidodendron fossil (Scale Tree Bark)
Lepidodendron (Lycophytina class)