Basalt
Mafic Igneous Rock (composed primarily of plagioclase feldspar and pyroxene)
Igneous
Category
Antropogenic Rock (Man Made)
Browse antropogenic rock (man made) specimens identified by the Rock Identifier community.
Sandstone (lithic wacke)
Arenite / Lithic Wacke (mostly SiO2 with rock fragments)
sedimentary
Porphyritic Basalt
Porphyritic Basalt (with Plagioclase phenocrysts)
igneous
Porphyritic Basalt (with Pyrolusite or Iron-oxide staining)
Porphyritic Basalt (Mafic Extrusive)
igneous
Sandstone
Arenite (SiO2 based with various mineral cements)
sedimentary
Glazed Ceramic Tile
Fused Silicate-Clay composite
Synthetic (Man-made material mimicking natural stone)
Druzy Quartz on Chert/Siltstone
Silicon Dioxide (SiO2) on Microcrystalline Silica/Siltstone matrix
sedimentary
Unidentified Rock Fragment
Unknown
Rock
Dyed Quartzite
Metamorphosed Quartz (SiO2) with synthetic pigment
metamorphic
Granite
Plutonic felsic rock (Quartz, Feldspar, Mica)
igneous
Slate
Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)
metamorphic
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
igneous
Basalt with Calcite Veins
Basalt (containing CaCO3 inclusions)
igneous
Painted River Rock
Anthropogenic-modified Siliciclastic Sedimentary Rock
Sedimentary
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)
Quartz Vein in Host Rock
Hydrothermal Quartz (SiO2) in Slates/Schists
metamorphic
Vesicular Basalt with Quartz/Chalcedony
Vesicular Basalt (primarily Plagioclase, Pyroxene, and Olivine with SiO2 infill)
igneous
Unakite
Epidotized Granite
metamorphic
Porphyritic Basalt (River Rock)
Porphyritic Basalt
igneous
Quartz Vein in Gneiss or Basalt
Milky Quartz (SiO2) within Metamorphic Host Rock
Metamorphic or Igneous with Mineral Inclusion
River Rocks (Black)
Various lithologies (e.g., basalt, chert, obsidian for black varieties), mechanically rounded clasts
Sedimentary
Sandstone (with potentially high Feldspar/Arkose content)
Clastic sedimentary rock (SiO2 dominated)
sedimentary
Druzy Quartz on Matrix (likely Limestone or Sandstone)
Silicon Dioxide (SiO2) with various trace impurities
Mineral on Sedimentary Rock
Sandstone (likely Arkosic)
Clastic Sedimentary Rock
sedimentary
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
sedimentary
Shale
Fissile mudstone (Shale)
sedimentary
Shale
Lutaceous sedimentary rock
sedimentary
Breciated Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Dark-colored Igneous Rock (likely Basalt or Diabase)
Basalt (extrusive igneous) or Diabase (intrusive igneous)
Igneous Rock
Sandstone (likely Greywacke or Lithic Sandstone)
Arenite / Wacke
sedimentary
Grey Limestone Pebble
Limestone (Calcium Carbonate - CaCO3)
sedimentary
Quartz Vein Rock
Quartz (Silicon Dioxide, SiO2)
igneous
Shale or Slate with Quartz Veins
Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins
Metamorphic, likely Sedimentary with Quartz veins
Slickenside
Tectonic Fault Scarp Surface
metamorphic
Basalt with Calcite Veins
Basalt (Mafic Volcanic Rock)
igneous
Basalt
Basalt (Mafic volcanic rock)
igneous
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Serpentinite
Serpentinite (complex silicate minerals including lizardite, chrysotile, and antigorite: (Mg,Fe)3Si2O5(OH)4)
metamorphic
Pink Granite
Phaneritic Plutonic Igneous Rock (high K-feldspar)
igneous