Pumice
Pumice (Amorphous volcanic glass)
Category
Browse sedimentary rock (specifically a concretion or possibly a geode) specimens identified by the Rock Identifier community.
Pumice
Pumice (Amorphous volcanic glass)
Conglomerate
Conglomerate (SiO2 primary clasts with lithic matrix)
Pumice
Pumice (Vesicular volcanic glass)
Sandstone (Ferruginous)
Arenite (SiO2 with Fe2O3 inclusions)
Gneiss
Gneiss
Desert Varnish on Sandstone
Ferromanganese coating on Quartz Arenite
Sandstone
Arenite (primarily SiO2)
Basalt with Plagioclase Feldspar
Basalt (mafic extrusive igneous rock) with plagioclase feldspar phenocrysts
Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Basalt
Basalt (extrusive volcanic mafic rock)
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Basalt
Mafic volcanic rock (formula varies by mineral content: Ca-plagioclase, Pyroxene, Olivine)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Sandstone (Greywacke/Siltstone variant)
Arenite / Wacke (SiO2 with diverse mineral inclusions)
Quartzite
Quartzite (primarily SiO2)
Sandstone
Arenite (primarily SiO2 with various cementing agents)
Concrete
Hydrated Portland Cement Aggregate Composite
Sandstone (likely Quartz Sandstone)
Arenite (composed primarily of SiO2)
Granite
Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Conglomerate
Conglomerate (clastic sedimentary rock)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Schist
Mica Schist (primarily Muscovite [KAl2(AlSi3O10)(OH)2] or Biotite)
Basalt
Extrusive Mafic Igneous Rock (composed primarily of Plagioclase, Pyroxene, and Olivine)
Quartz-veined Sedimentary Rock
Hydrothermally veined Clastic Sedimentary Rock (SiO2 veins in Matrix)
Breciated Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Dolomite
Dolomite (CaMg(CO3)2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic silicate with secondary mineral inclusions)
Quartz (Common Quartz Pebble)
Silicon Dioxide (SiO2)
Basalt
Extrusive Mafic Igneous Rock
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
Sandstone (likely Quartzose Sandstone)
Arenite (SiO2 predominantly)
Quartzite River Rock
Metamorphic Quartzite (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
White Marble
Recrystallized Calcite (CaCO3)
Yellow Chert or Jasper
Microcrystalline Quartz (SiO2)