Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides
mineral
Category
Mineral (Silicate Replaced Organic Material)
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Amethyst Sage Agate
Silicon Dioxide (SiO2) with trace minerals (Manganese/Iron oxides)
mineral
Sandstone (Ferruginous)
Arenite (with iron oxide cement, Fe2O3)
sedimentary
Amber
Succinurite (C10H16O)
mineraloid
Sandstone (Picture Sandstone)
Arenite (primarily SiO2)
sedimentary
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety
sedimentary
Sandstone (Ferruginous)
Arenite (Fe2O3 rich)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Coal (most likely Bituminous or Anthracite)
Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)
Sedimentary Rock
Sandstone (Ferruginous)
Sandstone (mainly SiO2 with Fe2O3 staining)
sedimentary
Chert (Nodule)
Chert (composition: SiO2)
sedimentary
Fluorite
Calcium Fluoride (CaF2)
mineral
Chalcedony (Botryoidal or Agate nodule)
Silicon Dioxide (SiO2)
mineral
Geode (Unopened)
Silica-rich concretion (SiO2)
sedimentary
Sandstone
Sandstone (lithified arenite/wacke)
Sedimentary Rock
Sandstone
Arenite (SiO2 primarily)
sedimentary
Sandstone
Arenite
sedimentary
Human Skin (Epidermis/Dermis)
Integumentary tissue (High content of hydroxyapatite in bones, though the surface is biological)
Mineral-like biological tissue
Garnet (Almandine/Pyrope variety)
Silicate mineral group; typically Fe3Al2(SiO4)3 (Almandine) or Mg3Al2(SiO4)3 (Pyrope)
mineral
Pink Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Amber (Copal)
Succinite (fossilized tree resin)
mineral
Moonstone
Adularia (orthoclase) or Albite (plagioclase), a potassium aluminum silicate of the feldspar group
Mineral
Asphalt (Bituminous pavement fragment)
Artificial conglomerate / Bitumen-Aggregate mixture
sedimentary
Ferruginous Chert
Microcrystalline Quartz (SiO2) with Iron Oxides
sedimentary
Amber
Succinite (a Fossilized Tree Resin); Chemical formula is approximately C10H16O
Organic mineraloid
Banded Chert
Cryptocrystalline Quartz (SiO2)
sedimentary
Banded Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
sedimentary
Turquoise (Green variety)
Hydrous phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
mineral
Sandstone (likely with Borings or Vesicular Basalt)
Clastic Sedimentary Rock (Sandstone)
sedimentary
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
sedimentary
Sandstone (with Iron concretions/staining)
Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (Lithic Sandstone)
sedimentary
Bicolor Quartz Pebble
Silicon Dioxide (SiO2) with mineral inclusions
mineral
Bumblebee Jasper
Calcite-bearing Volcanic Tuff containing Sulfur and Arsenic (Orpiment/Realgar)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
sedimentary
Limonite (Iron Ore)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
mineral
Cubic Zirconia (Simulated Diamond)
Zirconium dioxide (ZrO2)
mineral
Pegmatite (Granitic)
Granitic Pegmatite containing Quartz, Feldspar, and Tourmaline (Schorl)
igneous
Limonite-pseudomorph after Pyrite (Prophecy Stone)
Goethite and Limonite secondary minerals (FeO(OH)·nH2O) replacing Pyrite (FeS2)
mineral
Amber
Succinate (Fossilized Tree Resin)
mineraloid