Sandstone
Clastic sedimentary rock (primarily SiO2)
Category
Browse synthetic (not a rock or mineral) specimens identified by the Rock Identifier community.
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (with minor quartz and possible clay components)
Clastic Sedimentary Rock (SiO2 dominated)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cement)
Sandstone (with potential iron-oxide weathering)
Arenite (SiO2 based)
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (primarily SiO2)
United States Quarter Dollar
Cupronickel Clad Alloy (75% Copper, 25% Nickel over a 100% Copper core)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Granite
Granite
Granite
Granite (Phaneritic igneous rock)
Turquoise in Matrix
Hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Diorite
Intermediate plutonic igneous rock
Sandstone
Arenicola (comprising mostly Quartz, SiO2)
Granite
Phaneritic Plutonic Felsic Rock (K-Feldspar + Quartz + Plagioclase)
River/Stream Pebble
Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)
Quartz Geode
Silicon Dioxide (SiO2)
Schist
Mica Schist
Tiger's Eye (Brown/Dark variety)
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Quartz Druze
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Mica Schist
Mica Schist (primarily Muscovite and Biotite composition)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Gneiss
Gneissic Metamorphic Rock
Quartz (Druzy/Macro-crystalline)
Silicon Dioxide (SiO2)
Granite with Mafic Inclusions
Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)
Mexican Crazy Lace Agate
Silicon Dioxide (SiO2) with iron and aluminum inclusions
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Quartz Geode
Silicon Dioxide (SiO2) in a Secondary Formation
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
Sparkling Druzy Quartz on Matrix
Silicon Dioxide (SiO2) with iron oxide inclusions
Fluorite (Rainbow or Multi-colored Fluorite)
Fluorite (Calcium Fluoride - CaF2)
Granite
Granite (a felsic intrusive igneous rock)
Bauxite
Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)
Gneiss (Banded Gneiss)
Gneiss
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Diorite
Diorite (plutonic igneous rock)
Sandstone (with Lichen)
Arenite (primarily SiO2)