Chert (Pebble)
Microcrystalline to Cryptocrystalline Quartz (SiO2)
Category
Browse anthropogenic (man made material mimicking sedimentary rock) specimens identified by the Rock Identifier community.
Chert (Pebble)
Microcrystalline to Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Flint / Chert Nodules in Limestone
Cryptocrystalline Quartz (SiO2) within Carbonate Rock
Jasper
Jasper (Silicon Dioxide, SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Quartz-rich metamorphic fragment (likely mica schist)
Mica schist, probably muscovite–quartz schist
Blue Apatite
Calcium phosphate mineral, Ca5(PO4)3(F,Cl,OH)
Jasper and Agate (Polychrome Jasper / Mookaite variety)
Silicon dioxide (SiO2) microcrystalline quartz
Flagstone (Sandstone)
Clastic Sedimentary Rock (composed of quartz and feldspar)
Graywacke
Lithic Sandstone (Graywacke)
Petrified Wood
Silicified Wood (SiO2)
Chert / Flint Nodular Fragment
Microcrystalline quartz (SiO2)
Sandstone with Manganese Oxide Patina
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Banded)
Clastic sedimentary rock (primarily SiO2)
Red Sandstone
Arenite (Iron-rich Sandstone)
Petrified Wood
Silicified Wood (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Sandstone
Arenite (SiO2 based)
Red Sandstone
Arenite (Ferruginous Sandstone)
Travertine
Terrestrial Sedimentary Form of Calcium Carbonate (CaCO3)
Quartz Pebble (Chalcedony/Chert)
Silicon Dioxide (SiO2)
Ammonite Fossil (Small Pyritized or Calcitized Internal Mold)
Ammonoidea
Conical fossil shell or shell fragment
Likely a gastropod shell fragment; exact taxon indeterminate from the image
Zebra Rock / Zebra Marble
Banded Limestone-Marble Transition
Red Sandstone (Siltstone pebble)
Arenite / Siltstone (Silicon dioxide based with hematite impurities)
Sandstone (Red)
Arenite (primarily Quartz, SiO2, with Iron Oxide cement)
River Stone (River Pebbles)
Alluvial Deposit (typically Quartzite, Sandstone, or Granite clasts)
Milky Quartz
Silicon Dioxide (SiO2)
Chert (and Flint variant)
Microcrystalline Quartz (SiO2)
Ferruginous Sandstone
Ferruginous Quartz-Arenite
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Sandstone (with vugs or solution cavities)
Arenite (primarily Quartz and Feldspar with CaCO3 or SiO2 cement)
Polished yellow jasper or opaque chalcedony bead
Microcrystalline quartz (SiO₂), likely iron-oxide-stained jasper
Limestone (Weathered Pebble)
Calcium Carbonate (CaCO3) / Limestone
Quartz (Milky or Clear variety)
Silicon Dioxide (SiO2)
Fossilized Bone
Petrified Bone / Biogenic Sedimentary
Chalk / Sedimentary Limestone
Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock
Weathered limestone
Calcite-rich carbonate rock (mostly CaCO₃), possibly fossiliferous limestone
Banded Sandstone
Quartz Arenite (with iron oxide banding)
Feldspathic Gneiss (Granite Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)