Siltstone or Mudstone
Argillaceous sedimentary rock
Category
Browse sedimentary rock (specifically a concretion or possibly a geode) specimens identified by the Rock Identifier community.
Siltstone or Mudstone
Argillaceous sedimentary rock
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Basalt (Mafic volcanic rock)
Vesicular Basalt (Lava Rock)
Aphanitic Mafic Igneous Rock
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Septarian Nodule (Dragon Stone)
Septarian (composed of Calcite CaCO3, Aragonite CaCO3, and Limestone/Clay)
Lava Rock (Scoria)
Scoria (highly vesicular basaltic rock)
Vesicular Basalt with Amygdaloidal Infill
Basalt (Mafic Extrusive Igneous Rock)
Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
Basalt
Basalt (Mafic volcanic rock)
Basalt (Vesicular or Scoriaceous)
Aphanitic Mafic Volcanic Rock
Basalt Pebble
Basalt
Basalt
Basalt
Silty Shale
Silty Shale (Fissile Sedimentary Rock)
Shale (Ferruginous)
Laminated Mudrock (Siliciclastic Sedimentary Rock)
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
Basalt
Basalt
Basalt
Basalt (dominated by Plagioclase Feldspar and Pyroxene)
Basalt
Basalt (composition of Plagioclase feldspar and Pyroxene)
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 oxides)
Pumice
Pumice (a highly vesicular extrusive igneous rock)
Sandstone
Arenite (primarily SiO2)
Concrete with Exposed Aggregate
Anthropogenic conglomerate (Concrete)
Sandstone
Arenite
Sandstone
Arenite (primarily SiO2)
Basalt with Quartz/Epidote Vein
Mafic volcanic rock (formula primarily (Mg, Fe)2SiO4 and CaAl2Si2O8)
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica)
Pumice
Vesicular volcanic glass
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Amygdaloidal Basalt
Amygdaloidal Basalt (with secondary mineral infilling)
Limonite after Pyrite (Prophecy Stone or Ironstone Concretion)
Goethite/Limonite pseudomorph after Pyrite/Marcasite (FeO(OH)·nH2O)
Garnet Schist
Garnetiferous Micaceous Schist
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Basalt River Pebble
Basalt (Aphanitic Mafic Igneous Rock)
Basalt (River Stone)
Extrusive Mafic Igneous Rock (Basalt)
Basalt Pebble
Vesicular Basalt
Shiva Lingam
Cryptocrystalline Quartz (Jasperiod Silicate with Iron Oxide inclusions)
Fluorite Bracelet (light green beads) and possibly Lavender Jadeite (purple bead)
Fluorite: CaF₂ (Calcium Fluoride); Jadeite: NaAlSi₂O₆ (Sodium Aluminum Silicate)
Scoria (Lava Rock)
Vesicular Basalt / Scoria
Limestone
CaCO3 (Mainly Calcite or Aragonite)