Antropogenic Rock (Man Made)

Sandstone

Arenite (SiO2 primarily)

Sandstone (Yellow/Tan Sandstone)

Arenite (primarily Quartz, SiO2)

Red Sandstone

Arenite (primarily Quartz, SiO2, with Iron Oxide cementing agent)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (SiO2 based)

Sandstone (likely Quartzose)

Arenite (primarily SiO2)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Sandstone with Calcite Vein

Clastic sedimentary rock (primarily SiO2) with Calcium Carbonate (CaCO3) infilling

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Sandstone (Pebble)

Arenite / Clastic Sedimentary Rock

Piddock-bored Mudstone

Lutite (Siltstone or Mudstone) with Pholad borings

Sandstone (Micaceous)

Arenite (composed primarily of SiO2)

Granite / Quartz Vein Rock

Granitoid with Quartz (SiO2)

Granite

Granite (Mainly Quartz SiO2, K-Feldspar KAlSi3O8, and Plagioclase)

Quartzite

Quartzite (primarily SiO2)

Ruby in Zoisite (Anyolite)

Anyolite (Combination of Corundum and Zoisite)

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Sandstone (likely Graywacke or Arkose variant)

Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)

Vesicular Basalt

Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)

Sandstone (with Limonite staining)

Arenite (primarily SiO2 with FeO(OH)·nH2O)

Sandstone

Arenite (predominantly SiO2)

Blue Chalcedony

Silicon Dioxide (SiO2)

Sandstone

Arenite (Siliclastic sedimentary rock), SiO2 + various minerals

Limestone

Calcium Carbonate (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Basalt with Olivine Phenocrysts

Porphyritic Basalt (containing Mg2SiO4 - Fe2SiO4)

Granite Cobble / Rounded Granite River Rock

Granite

Shale

Shale (clastic sedimentary rock)

River/Stream Pebble

Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)

Sandstone

Sandstone (lithified sand)

Chert Pebble Map

Microcrystalline Quartz (SiO2)

Quartz vein in metamorphic rock

Crystalline Silicon Dioxide (SiO2) in Host Rock

Porphyritic Rhyolite (Cookie Stone)

Porphyritic Rhyolite (SiO2, with phenocrysts)

Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

Sandstone

Arenite (primarily SiO2)

Sandstone (specifically Flagstone)

Arenite (primarily composed of SiO2)

Folded Schist / Gneiss (Metamorphic Rock)

Regional Metaphoric Folded Outcrop (predominantly Schist/Gneiss)

Milky Quartz

Silicon Dioxide (SiO2)

Coquina / Shelly Limestone

Bioclastic Limestone (composed of CaCO3)

Sandstone

Arenite (SiO2 predominantly)

Quartz Geode

Silicon Dioxide (SiO2)