Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Basalt
Mafic Igneous Rock
igneous
Sandstone (Ferruginous)
Clastic Sedimentary Rock (SiO2 with Fe2O3/FeOOH cement)
sedimentary
Granite
Phaneritic Igneous Rock (Granitic)
igneous
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Basalt (Weathered Pebble)
Extrusive mafic rock (primarily Plagioclase Feldspar and Pyroxene)
igneous
Basalt
Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
igneous
Sandstone Concretion
Clastic Sedimentary Concretion (primarily SiO2 with Fe2O3 cement)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (Vitreous to Aphanitic Mafic Igneous Rock)
igneous
Chalcedony in Limestone Host Rock
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
Mineral within Sedimentary Rock
Quartz with Iron Staining
Silicon Dioxide (SiO2) with Hematite/Limonite inclusions
mineral
Quartzite with inclusions
Metamorphosed Quartz-rich Rock (SiO2)
metamorphic
Cinnabar in Quartz
Silicon Dioxide (Quartz, SiO2) with Mercury Sulfide inclusions (Cinnabar, HgS)
mineral
Sandstone (Ferruginous)
Sandstone (mainly SiO2 with Fe2O3 staining)
sedimentary
Marble
Recrystallized Carbonate Rock (CaCO3)
metamorphic
Quartz Vein with Iron Staining
Silicon Dioxide (SiO2)
mineral
Jasper
Silicon Dioxide (SiO2)
mineral
Red Shale
Fissile Siliciclastic Sedimentary Rock
sedimentary
Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color
Silicon Dioxide (SiO2), a variety of Chalcedony
Sedimentary Rock
Chert (Mudstone)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
Mineral (occurring as a rolled clast)
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 principal component)
sedimentary
Greenstone
Greenschist (metamorphosed mafic igneous rock)
metamorphic
Lapis Lazuli
Lapis Lazuli (a rock, not a single mineral; primary mineral is Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Metamorphic rock
Serpentinite
Serpentinite (composed primarily of Serpentine minerals: Mg3Si2O5(OH)4)
metamorphic
Copper Ore with Chrysocolla and Azurite
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla) / Cu3(CO3)2(OH)2 (Azurite)
mineral
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
sedimentary
Bauxite
Bauxite (Al2O3·2H2O)
sedimentary
Schist
Mica Schist
metamorphic
Eclogite garnet in matrix
Eclogite (Garnet-Omphacite rock)
metamorphic
Granite Thin Section
Granitic rock (Phaneritic texture)
igneous
Diorite
Plutonic Igneous Rock (Intermediate Composition)
Igneous
Clear Quartz Crystal
Quartz (Silicon Dioxide, SiO2)
mineral
Red Sandstone
Arenite (primarily composed of SiO2 with Fe2O3 cement)
sedimentary
Basalt
Extrusive Mafic Igneous Rock
igneous
Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles
Mixed gemstones (primarily Silicon Dioxide - SiO2)
mineral
Tufa (Limestone)
Calcareous Tufa (CaCO3)
sedimentary
Geode (Chert or Quartz Nodule)
Silicon Dioxide (SiO2)
sedimentary
Quartz pebble (Quartztite fragment)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble (Geode-like)
Silicon Dioxide (SiO2)
Mineral