Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
Category
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
Granite (Pink/Potassium-rich)
Phaneritic Plutonic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
Fossiliferous Chert (Chert with Crinoid Stem Impression)
Chert (SiO2) with fossil Anthozoan or Crinoid columnals
Orange Calcite (Banded Calcite)
Calcium Carbonate (CaCO3)
Amethyst
Crystalline Silicon Dioxide with Iron impurities (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline quartz (SiO2)
Sandstone (Ferruginous)
Arenite (iron-rich)
Jasper (Petrified Wood Variety)
Silicon Dioxide (SiO2)
Banded Calcite (Green Onyx)
Calcium Carbonate (CaCO3)
Black Opal
Hydrated Silica (SiO2·nH2O)
Chert (specifically Flint or Novaculite variant)
Chert (Microcrystalline Quartz, SiO2)
Sandstone
Arenite (SiO2 principal component)
Sandstone (Greywacke/Siltstone variant)
Arenite / Wacke (SiO2 with diverse mineral inclusions)
Sandstone (Greywacke/Lithic Sandstone)
Arenite (composed primarily of SiO2)
Sandstone (Ferruginous)
Arenite (Fe-bearing Clastic Sedimentary Rock)
Chert (Smooth River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Quartzite
Quartzite (primarily SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Sandstone (Weathered Coastal Boulder)
Arenite (composed primarily of SiO2)
Chalcedony on Matrix
Silicon Dioxide (SiO2)
Sandstone (Water-worn Cobble)
Arenite (variable composition, primarily SiO2)
Chalcedony (Common Agate)
Silicon Dioxide (SiO2)
Quartz / Common Agate
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Amethyst (variety of Quartz, SiO2)
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
Marble (Carrara Marble style)
Recrystallized Calcite (CaCO3)
Sandstone
Arenite (SiO2 based)
Sandstone (Stream-rounded)
Arenite (SiO2 based)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Milky Quartz with Mineral Inclusions
Silicon Dioxide (SiO2) with miscellaneous inclusions
Sandstone
Arenite (primarily SiO2)
Ruby
Corundum (Al2O3 with Chromium impurities)
White Marble
Recrystallized Calcite (CaCO3)
N/A (Non-Geological Object)
Chert (and Chert Geode)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)