Pumice
Pumice (a highly vesicular volcanic rock)
igneous
Category
Sedimentary Rock (Specifically A Concretion Or Possibly A Geode)
Browse sedimentary rock (specifically a concretion or possibly a geode) specimens identified by the Rock Identifier community.
Gabbro
Gabbro (mafic intrusive igneous rock)
igneous
Basalt (River Pebble)
Basalt (Mafic Extrusive Igneous Rock)
igneous
Septarian Nodule (Dragon Stone)
Septarian Nodule (containing Calcite, Aragonite, and Limestone/Clay)
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2)
sedimentary
Basalt
Basalt (Mafic Extrusive Igneous Rock)
igneous
Basalt
Basalt (principally composed of pyroxene and plagioclase feldspar)
igneous
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
sedimentary
Chert (Jasper/Flint Pebble)
Microcrystalline quartz (SiO2)
sedimentary
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Basalt
Basalt (Aphanitic mafic volcanic rock)
igneous
Chert (Chalcedony/Flint)
Silicon Dioxide (SiO2)
sedimentary
Sandstone (likely Arkosic or Lithic Sandstone)
Arenite (SiO2 based with mineral inclusions)
sedimentary
Agate (specifically Moss or Plume Agate nodding toward Agatized Wood)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz (Chalcedony)
mineral
Sandstone (Quartzose Sandstone)
Clastic Terrigenous Sedimentary Rock (primarily SiO2)
sedimentary
Shale
Fissile Mudstone (Shale)
sedimentary
Chert (and Flint)
Silicon dioxide (SiO2) - Microcrystalline or Cryptocrystalline Quartz
sedimentary
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
sedimentary
Sandstone (River Rock)
Arenite (composed primarily of SiO2)
sedimentary
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite impurities
sedimentary
Grey Limestone Pebble
Limestone (Calcium Carbonate - CaCO3)
sedimentary
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
igneous
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Satin Spar (Selenite)
Gypsum (CaSO4·2H2O)
mineral
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Laterite
Laterite (primarily composed of hydrated oxides of iron and aluminum)
Sedimentary Rock (as a residual soil/rock, it's often considered a type of sedimentary rock due to its formation from weathering, though it can cross into soil science)
Red Scoria (Lava Rock)
Scoria (Vesicular Basalt)
igneous
Basalt
Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
igneous
Slag (Industrial Glass/Metal)
Ferrous slag or Glassy silicate byproduct
Antropogenic rock (Man-made)
Sandstone (likely Calcareous or Quartz-rich)
Arenite (SiO2 based typically)
sedimentary
Basalt
Mafic volcanic rock, primarily composed of Plagioclase, Pyroxene, and Olivine
Igneous
Basalt (River or Beach Pebble)
Basalt (Mafic Extrusive Igneous Rock)
igneous
Vesicular Basalt
Vesicular Basalt (Aphanitic Mafic Rock)
igneous
Pumice
Pumicite (Amorphous Volcanic Glass)
igneous
Sandstone (Weathered Pebble)
Arenite (composed primarily of SiO2)
sedimentary
Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
igneous
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Granite
Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)
igneous
Pumice
Vesicular Rhyolite or Andesite (Amorphous volcanic glass)
igneous
Chert (Gravel)
Silicon Dioxide (SiO2)
sedimentary
Crushed Stone / Greywacke
Greywacke (Indurated Sandstone)
sedimentary