Chert (Flint)
Cryptocrystalline Quartz (SiO2)
sedimentary
Category
Not A Rock (Synthetic Material)
Browse not a rock (synthetic material) specimens identified by the Rock Identifier community.
Learn about Not A Rock (Synthetic Material) in the encyclopedia
View all →
Sandstone
Arenite
sedimentary
Sandstone
Arenite
sedimentary
Quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly microcrystalline quartz (SiO₂), with possible mica or iron-oxide impurities
metamorphic
Fossil Coral
Rugose Coral / Hexagonaria (CaCO3)
fossil
Sandstone
Sedimentary Rock (Quartz arenite or arkose)
sedimentary
Sandstone
Sandstone (SiO2 predominant)
sedimentary
Diorite (River Cobble)
Intermediate phaneritic igneous rock
igneous
Sandstone Pebble
Ferruginous Sandstone (SiO2 with Fe2O3)
sedimentary
Porphyritic Basalt (or Porfido / Porphyry Beach Pebble)
Porphyritic Basalt / Andesite
igneous
Sandstone (Ferruginous)
Arenite (with Iron Oxide cement)
sedimentary
Amygdaloidal Basalt with Quartz
Basalt with Secondary Mineral Infilling
igneous
Quartz (River Pebble)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone (lithic wake or graywacke)
Clastic sedimentary rock (primarily quartz and lithic fragments)
sedimentary
Jasper River Stone
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Vesicular Basalt (Lava Rock)
Vesicular Basalt (comprising plagioclase feldspar and pyroxene group minerals)
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Sandstone Pebble (River Rock)
Arenite (primarily SiO2)
sedimentary
Sandstone (likely Quartzose)
Sandstone (Principally SiO2)
sedimentary
Sandstone (likely Arkosic or Lithic Sandstone)
Arenite (SiO2 based with mineral inclusions)
sedimentary
Sandstone (Quartzose)
Arenite (SiO2 based)
sedimentary
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
sedimentary
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
metamorphic
Quartz Vein in River Siltstone
Crystalline Quartz (SiO2) in Siliclastic Matrix
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
River Pebble (Quartz/Jasper)
Silicon Dioxide (SiO2)
sedimentary
Clear Quartz / Diamond (untested)
Silicon Dioxide (SiO2) or Carbon (C)
mineral
Granodiorite
Granodiorite
igneous
Slate
Metamorphic Pelitic Rock
metamorphic
Sandstone
Arenite (primarily SiO2)
sedimentary
Gneiss
Gneissic Metamorphic Rock
metamorphic
Sandstone
Arenite (specifically Quartz Arenite)
sedimentary
Mottled gabbro or diorite pebble
Coarse-grained mafic/intermediate intrusive rock; chiefly plagioclase feldspar plus pyroxene, with possible amphibole or biotite
igneous
River Pebble (Greywacke / Basalt Pebble)
Indeterminate Rounded Pebble (composed of quartz, feldspar, or mafic minerals)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Sandstone Pebble
Quartz Arenite / Sandstone
sedimentary
Sandstone
Sandstone (SiO2 dominated)
sedimentary
Sandstone
Arenite (primarily Quartz and Feldspar composition)
sedimentary
Sandstone
Arenite (SiO2 based with mineral cements)
sedimentary
Sandstone (with Calcite or Silica veins)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Sandstone
Arenite (specifically Quartz Arenite)
sedimentary