Limestone
Calcium carbonate ( преимущественно CaCO3)
sedimentary
Category
Not A Natural Rock (Man Made Composite)
Browse not a natural rock (man made composite) specimens identified by the Rock Identifier community.
Yooperlite (Sodalite-bearing Syenite)
Fluorescent Sodalite-bearing Syenite
igneous
Granite
Phaneritic Plutonic Felsic Rock (Granite)
igneous
Carnelian Agate
Silicon Dioxide (SiO2) - Variety: Chalcedony
mineral
Iron Ore / Ironstone Concretion
Mixture of iron oxide/hydroxide minerals, likely some combination of Hematite (Fe2O3), Goethite (α-FeOOH), and Limonite (a general term for hydrated iron oxides of variable composition) or potentially Bauxite (a mixture of aluminum hydroxides, often with iron oxides, (Al(OH)3) and FeO(OH)). The visual characteristics strongly suggest iron-rich material.
Mineral, specifically an iron ore
Goethite
Goethite (α-FeO(OH))
Mineral
Sodalite
Na8(Al6Si6O24)Cl2
mineral
White Moonstone (Scolicite or White Feldspar var. )
Lattice-structure Silicate (KAlSi3O8)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Magnetite / Iron Ore
Magnetite (Fe3O4)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
K2 Jasper (Beads)
Granodiorite with Azurite and Malachite
igneous
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Soapstone
Steatite (composed primarily of Talc: Mg3Si4O10(OH)2)
metamorphic
Chert (and Jasper blend)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 staining)
sedimentary
Granite and Igneous Mix
Phaneritic Felsic to Mafic Intrusive Rocks
igneous
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Mineraloid
Sandstone
Arenite (SiO2 based)
sedimentary
Moonstone (Tumbled)
Orthoclase Feldspar (KAlSi3O8) with inclusions of Albite
mineral
Conglomerate
Conglomerate (Sedimentary Clastic Rock)
sedimentary
Quartz (likely Milky Quartz or Chalcedony)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Quartzite
Quartzite (SiO2)
metamorphic
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz (likely milky/gray variety)
Quartz (SiO₂)
Mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Greenstone
Greenschist (metamorphosed mafic igneous rock)
metamorphic
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Porphyritic Basalt
Basalt (with plagioclase phenocrysts)
igneous
Calcite
Calcite (Mineral, Calcium Carbonate - CaCO3)
Mineral
Quartz
Quartz (SiO₂)
mineral
Sandstone Clast
Arenite (primarily SiO2)
sedimentary
Unakite
Unakite Epidosite (composite of Epidote, Orthoclase, and Quartz)
metamorphic
Limonite (Iron Ore Congcretion)
Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)
mineral
Quartzite (Iron-stained)
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (primarily SiO₂)
metamorphic
Sandstone (Weathered Cobble)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Carnelian Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
mineral
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Limestone with Calcite Crystals
Calcium Carbonate (CaCO3)
sedimentary