Chert (Jasper variety)
Silicon Dioxide (SiO2)
Category
Browse organic (non rock) specimens identified by the Rock Identifier community.
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Gneiss (specifically a Banded Gneiss cobble)
Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)
Chert (Jasper/Agate variety)
Silicon Dioxide (SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert / River Pebble
Silicon Dioxide (SiO2)
Red Quartzite (Tumbled Pebble)
Quartzite (primarily SiO2 with hematite inclusions)
Quartzite with inclusions
Quartzite (primarily SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Fossil Coral (Rugose Coral Fragment)
Rugosa (extinct order of solitary and colonial corals)
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Quartzite River Cobble
Quartzite (primarily SiO2)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2)
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
Pumice
Pumice (Vesicular Felsic Glass)
Chert (Holey Stone)
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (SiO2)
Glauconitic Sandstone
Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Pyrite Geode (Sparkling Druzy)
Iron Sulfide (FeS2) in Sedimentary Nodule
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Conglomerate
Conglomerate (Sedimentary Clastic Rock)
Agate (Moss or Dendritic Agate)
Chalcedony (Silicon Dioxide, SiO2)
Obsidian
Obsidian (principally SiO2)
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
Snowflake Obsidian
Vitreous Volcanic Rock (Amorphous Silicate), SiO2
Flower Jasper
Agatized Fossil Coral / Chalcedony (SiO2)
Chert (Jasper)
Silicon dioxide (SiO2)
Chert (Flint)
Chert (SiO2)
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
Green Slag Glass (Cullet)
Amorphous Silica (Industrial Glass Byproduct)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Man-made Carved Stone (Scream Mask/Skull motif)
Carved Soapstone or Serpentine-rich rock
Chert (Field Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Jasper
Silicon dioxide (SiO2)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Quartzite River Rock
Quartzite (SiO2)
Quartzite
Quartzite (primarily SiO2)