Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Category
Browse not a rock (synthetic material) specimens identified by the Rock Identifier community.
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Sandstone (Micaceous/Feldspathic variant)
Arenite (specifically subarkose or lithic arenite)
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)
Sandstone (with Liesegang rings or Oxidation)
Arenite (primarily Quartz SiO2 with Iron Oxide Fe2O3 staining)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Limestone
Calcium carbonate (CaCO3)
Granite (with alteration)
Granite (Felsic intrusive igneous rock)
Sandstone
Arenite (primarily composed of SiO2 - Silicon Dioxide)
Chert (Jasper)
Silicon dioxide (SiO2)
Quartzite River Rock
Quartzite (primarily SiO2)
Chert (or Chalcedony) Nodule
Microcrystalline Quartz (SiO2)
Chert (specifically Jasper/Flint)
Microcrystalline Quartz (SiO2)
Smoky Quartz with Feldspar
Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)
Gray Quartzite with Quartz Veining
Metamorphosed Quartz-rich Sandstone
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (Lithic Sandstone)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Sandstone (lithified arenite/wacke)
Conical fossil shell or shell fragment
Likely a gastropod shell fragment; exact taxon indeterminate from the image
Quartzite with Hematite staining
Metamorphic Quartzite (SiO2)
Brown Agate
Cryptocrystalline Quartz (SiO2)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2)
Iron-stained chert or jasper pebble
Microcrystalline quartz (SiO₂), likely hematite/goethite-bearing
Sandstone
Arenite (SiO2 primarily)
Sandstone (Ferruginous)
Arenite (with high iron oxide content)
Siltstone with flute casts or scratch marks
Clastic Sedimentary Rock (Siltstone/Fine-grained Sandstone)
Granite
Granite (Felsic Plutonic Rock)
Sandstone (Yellow/Siltstone variant)
Arenite (SiO2 primarily)
Sandstone (River Cobble)
Sandstone (primarily composed of silica, SiO2)
Schist
Schist (Crystalline metamorphic rock)
Quartz
Silicon Dioxide (SiO2)
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Yellow Jasper
Jasper, a microcrystalline variety of Quartz (SiO2) with iron inclusions
Travertine (Tufa)
Chemical Limestone (CaCO3)
Serpentinite
Serpentinite (Hydrous magnesium iron phyllosilicate)
Granodiorite / Granite
Granodiorite (containing Quartz SiO2, Plagioclase Feldspar, and Biotite)
Shiva Lingam
Cryptocrystalline Quartz (Jasproid/Sandstone) with Iron Oxide (Fe2O3)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Brecciated jasper
Silica-rich cryptocrystalline quartz (SiO₂), commonly with iron-oxide and clay-rich matrix
Quartzite
Quartzite (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)