Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
sedimentary
Category
Organic Structure (Not A Rock)
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Peacock Ore
Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with iridescent tarnish
mineral
Basalt with Quartz/Calcite Veins
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Dendritic Agate / Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Red Jasper with Quartz Veining
Jasper (Silicon Dioxide, SiO2) with Quartz (SiO2) inclusions
sedimentary
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
mineral
Quartz Vein with Host Rock (Greywacke/Siltstone)
Silicon Dioxide (SiO2) within Clastic Sedimentary/Metamorphic Matrix
metamorphic
Unakite
Epidotized Granite
metamorphic
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartz on Basalt
Silicon Dioxide (SiO2) on Mafic Igneous Rock
Mineral on Igneous Rock
Quartz Vein in Metamorphic Rock
Silicon Dioxide (SiO2) within Metasedimentary host
metamorphic
Chert (variant Flint)
Silicon Dioxide (SiO2)
sedimentary
Vesicular Basalt (or Scoria)
Vesicular Basalt (Aphanitic-vesicular volcanic rock)
igneous
Chert (specifically Jasper/Flint pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert Pebble (Jasper variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint variety)
Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2
sedimentary
Granite
Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)
igneous
Unakite
Unakite (Altered Granite composed of Orthoclase KAlSi3O8, Epidote Ca2(Al, Fe)3(SiO4)3(OH), and Quartz SiO2)
metamorphic
Shale
Shale (Lutite)
sedimentary
Chert (Jasper/Flint variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Travertine (Calcareous Tufa)
Calcium Carbonate (CaCO3)
sedimentary
Greywacke (River Pebble with Quartz Veins)
Greywacke (Indurated Sandstone); Veins: SiO2 (Quartz)
sedimentary
Quartz Vein in River Siltstone
Crystalline Quartz (SiO2) in Siliclastic Matrix
sedimentary
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety
sedimentary
Snowflake Obsidian
Volcanic glass containing Spherulitic Cristobalite (SiO2)
igneous
Marble
Metamorphic Limestone (CaCO3)
metamorphic
Sandstone
Arenite (primarily SiO2)
sedimentary
Porphyritic Basalt (River Rock)
Porphyritic Basalt
igneous
Pink Quartzite
Quartzite (SiO2 with minor iron oxide impurities)
metamorphic
Chert (specifically Chert Nodule/Flint)
Chert (Silicon Dioxide, SiO2)
sedimentary
Unakite
Unakite (altered granitic rock)
metamorphic
Unakite
Epidotized Granite
metamorphic
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Painted River Pebble (likely Basalt or Greywacke)
Aphanitic Lithic Clast with Anthropogenic Pigment coating
Sedimentary or Igneous