Chert (Beach Pebble)
Silicon Dioxide (SiO2)
Category
Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.
Chert (Beach Pebble)
Silicon Dioxide (SiO2)
White Marble
Recrystallized Calcite (CaCO3)
Shale with Iron Staining
Fissile Argillaceous Sedimentary Rock
Limestone
Sedimentary Calcite (CaCO3)
Banded calcite (travertine or calcite-rich carbonate)
Calcite, CaCO₃; likely banded travertine or recrystallized limestone
Polished fossiliferous limestone pebble
Fossiliferous micritic limestone, chiefly calcite (CaCO₃)
Chert Pebble (with fossil shell fragment)
Microcrystalline Quartz (SiO2) with Calcified Invertebrate Impression
Siltstone with iron staining
Siltstone (primarily SiO2 with FeO(OH) coatings)
Gray chalcedony (microcrystalline quartz)
Chalcedony, SiO₂; likely common gray/blue-gray variety
Quartz Geode
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Red Siltstone (or Red Shale)
Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)
Quartz Veined Mudstone
Metasedimentary rock with Quartz (SiO2) veins
Weathered limestone fragment
Calcitic limestone (mostly CaCO₃; possibly micritic limestone)
Likely weathered chert or flint
Microcrystalline quartz (SiO₂), probably chalcedony/chert
Limestone River Pebble
Calcium carbonate (CaCO3) - micritic limestone
Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
Chert Pebble (Jasper variety)
Microcrystalline Quartz (SiO2)
Red Sandstone
Sedimentary Clastic Rock (Quartz Arenite)
Sandstone
Sedimentary Rock (Quartz Sandstone)
Chert (Iron-Stained)
Microcrystalline Silica (SiO2)
Tumbled milky quartz (likely quartz pebble)
Quartz, silicon dioxide (SiO₂)
Chert with Quartz Veining
Microcrystalline Silica (SiO2)
Limestone with Stylolites
Calcareous sedimentary rock (CaCO3)
Tumbled honey-brown chalcedony or agate
Microcrystalline quartz (SiO₂), likely chalcedony; exact identification requires testing
Sandstone
Arenite (SiO2 based)
Conglomerate (Puddingstone)
Conglomerate (specifically, clastic sedimentary rock)
Sandstone
Sandstone (Quartz-rich sedimentary rock)
Sandstone Pebble
Sedimentary Rock (Quartzose Sandstone)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Dendritic Siltstone
Siltstone with Manganese Dendrites (MnO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Geode (Chert/Quartz)
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline quartz (SiO2)
Shale
Laminated Mudstone
Petrified Wood
Silicified Wood (primarily Quartz or Chalcedony, SiO2)
Quartzite Conglomerate
Conglomerate (SiO2 rich)
Sandstone
Arenite (SiO2 based sedimentary rock)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Quartz Geode Fragment
Crystalline Silicon Dioxide (SiO2)
Sandstone
Sandstone (SiO2-rich framework with variable matrix)
Sandstone
Arenite (major component SiO2)