Yellow Chert Pebbles/Yellow Jasper
Microcrystalline Quartz (SiO2) with Goethite or Limonite inclusions
Category
Browse sedimentary (with some aspects of mineral replacement) specimens identified by the Rock Identifier community.
Yellow Chert Pebbles/Yellow Jasper
Microcrystalline Quartz (SiO2) with Goethite or Limonite inclusions
Chert
Chert (Microcrystalline Quartz, SiO2)
Flint (or Chert)
Silicon dioxide (Microcrystalline Quartz, $SiO_2$)
Flint / Chert
Microcrystalline Quartz (SiO2)
Chert / Flint
Silicon dioxide (SiO2)
Flint
SiO2 (Microcrystalline Quartz / Chert)
Flint (or Chert)
Silicon dioxide (SiO2) microcrystalline quartz
Flint
SiO2 (Microcrystalline Quartz / Chert)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Limonitic Chert)
Microcrystalline Quartz (SiO2)
Fossil Coral
Hexagonaria / Rugosa / Scleractinia
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Potassium Feldspar
Orthoclase (KAlSi3O8)
Sandstone
Arenite (clastic sedimentary rock)
Fossil Coral
Rugosa or Tabulata coral fossil
Magnetite (Lodestone)
Magnetite (Fe3O4)
Clear Quartz
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Banded sandstone pebble
Quartz-rich lithic sandstone; exact provenance and composition require testing
Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone or Limonite (FeO(OH)·nH2O)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Magnetite
Magnetite (Iron(II,III) oxide, Fe3O4)
Sandstone
Arenite
Fluorescent tumbled mineral specimen, likely calcite
Calcite (calcium carbonate, CaCO₃), probable UV-fluorescent variety
Yellow Chert (Gold-colored River Pebble)
Microcrystalline Quartz (SiO2) with Limonite/Goethite staining
Petrified Wood
Silicified Wood (SiO2)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Sandstone (likely Arkosic)
Clastic Sedimentary Rock
Gneiss
Gneiss
Fossilized mammalian tooth fragment
Likely a fossil molar or premolar; exact taxon cannot be determined from the image
Sandstone
Sandstone (clastic sedimentary rock, predominantly SiO2)
Limonite-stained Chert
Microcrystalline Quartz (SiO2) with Goethite/Limonite (FeO(OH)·nH2O)
Concretion in Shale
Siltstone/Shale with Siderite or Calcareous concretions
Flint / Chert with Cortex
Microcrystalline Quartz (SiO2)
Jasper / Chert (river tumbled)
Microcrystalline Quartz (SiO2)
Flint
SiO2 (Microcrystalline Quartz / Chert)
Muscovite Schist
KAl2(AlSi3O10)(OH)2 (Muscovite) in Schist Matrix
Chert (Flint)
Microcrystalline Quartz (SiO2)
Polished banded pebble, likely quartz-veined chert or jasper
Microcrystalline quartz (SiO₂), possibly chert/jasper with a quartz or chalcedony vein
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)