Basalt
Basalt (principally Plagioclase and Pyroxene)
igneous
Category
Not A Natural Rock
Browse not a natural rock specimens identified by the Rock Identifier community.
Basalt
Basalt
igneous
Schist
Mica Schist
metamorphic
Serpentine
Serpentinite (a rock composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite; general formula (Mg, Fe)3Si2O5(OH)4)
metamorphic
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Quartz on Greenstone
Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit
metamorphic
Serpentinite (Serpentine Rock)
Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.
Metamorphic
Rose Quartz
Silicon Dioxide (SiO2)
mineral
Jasper with Quartz inclusions
Silicon Dioxide (SiO2) with impurities
sedimentary
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Opaque cryptocrystalline variety of Quartz
sedimentary
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
mineral
Mixed Tumbled Gemstones and River Rocks
Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)
Mixed (Igneous, Sedimentary, Metamorphic, and Minerals)
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone (with Lichen)
Arenite (composed primarily of SiO2)
sedimentary
Scoria (with likely iron oxidation)
Scoria (Basaltic Scoria)
igneous
River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
mixed
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
metamorphic
Quartzite Pebble (River Rock)
Quartzite (mainly SiO2)
metamorphic
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
igneous
Granite Cobble
Plutonic Igneous Rock (Granitic)
igneous
Jasper (Yellow/Brown variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Yellow Jasper
Silicon Dioxide (SiO2) - Impure Cryptocrystalline Quartz
sedimentary
Quartz Vein in Host Rock (Gabbro or Basalt)
Silicon Dioxide (SiO2) with Mafic Silicates
metamorphic/igneous
Sandstone (clastic)
Clastic Sedimentary Rock (primarily composed of SiO2)
sedimentary
Vesicular Basalt (or Scoraceous Basalt)
Basalt with vesicular texture
igneous
Vesicular Basalt (or Scoria)
Vesicular Basalt
igneous
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 + varied clasts)
sedimentary
Basalt Scoria
Vesicular Basalt
igneous
Moss Agate
Silicon Dioxide (SiO2) with inclusions
mineral
Quartz (Milky/Common Quartz)
Silicon Dioxide (SiO2)
mineral
Agate Geode / Nodular Chalcedony
Silicon Dioxide (SiO2) with impurities
mineral
Gastropod Steinkern (Internal Mold Fossil)
Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix
sedimentary
Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
sedimentary
Chert (Common Opal/Agate mixture)
Microcrystalline Quartz (SiO2)
sedimentary
Tiger's Eye (Rough)
Pseudomorph of Quartz after Crocidolite (SiO2)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Quartz (Pebble)
Quartz (SiO₂)
Mineral
Fluorite
Calcium Fluoride (CaF2)
mineral