Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
Category
Browse man made material (jewelry, metal alloy) specimens identified by the Rock Identifier community.
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
Granite
Course-grained intrusive igneous rock
Granite River Rock
Phaneritic Felsic Igneous Rock (Granite)
Aragonite Star Cluster (or Aragonite Sputnik)
Aragonite (Orthorhombic Calcium Carbonate, CaCO3)
Limestone (Cliff Formation)
Limestone (predominantly CaCO3 as calcite)
Sandstone
Arenite
Quartz (vein quartz)
SiO2 (Silicon Dioxide)
Ocean Jasper (Sea Jasper)
Spherulitic Chalcedony (SiO2)
Banded Agate (Brazilian Agate Slice)
Chalcedony (Silicon Dioxide / SiO2)
Mahogany Obsidian
Obsidian (SiO2 + Fe2O3)
Sandstone
Quartz Sandstone (predominantly)
Granite
Granitoid
Coal (most likely Bituminous or Anthracite)
Coal (organic sedimentary rock)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Coquina
Coquina (a type of limestone)
Sandstone
Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)
Red Sandstone
Arenite (primarily Quartz and Feldspar with Iron Oxide cement)
Schist
Schist
Limestone Pebble
Sedimentary Calcium Carbonate (CaCO3)
Snowflake Obsidian
Spherulitic Volcanic Glass (SiO2 + impurities)
Druzy Quartz Geode (likely Smokey Quartz variety)
Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.
Carnelian (a variety of Chalcedony)
Silicon Dioxide (SiO2) with iron oxide impurities
Honey Calcite
Calcium Carbonate (CaCO3)
Ocean Jasper
Spherulitic Chalcedony (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese
Jasper (specifically Red Jasper)
Silicon Dioxide with Iron Oxides (SiO2 + Fe2O3)
Agate (specifically Moss or Plume Agate nodding toward Agatized Wood)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz (Chalcedony)
Agate Geode
Chalcedony (SiO2 - Silicon Dioxide)
Banded Agate (River Stone)
Agate (Silicon Dioxide - SiO2)
Sandstone
Arenite
Sandstone (likely Graywacke or Arkosic varieties)
Arenite (composed primarily of SiO2)
Wallboard/Drywall (Gypsum-based)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Sandstone
Sandstone (composed primarily of sand-sized minerals or rock grains)
Granite
Granite (Felsic Plutonic Rock)
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Amethyst
SiO2 (Silicon Dioxide) - Purple variety of Crystalline Quartz
Granite
Phaneritic Plutonic Felsic Rock (SiO2 > 69%)
Limestone (with potential fossil inclusions)
Calcium Carbonate (CaCO3)