Gneiss
Gneissic Metamorphic Rock
metamorphic
Category
Man Made Material (Simulated Mineral)
Browse man made material (simulated mineral) specimens identified by the Rock Identifier community.
Halite (Rock Salt)
Halite; NaCl (Sodium Chloride)
Mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Peridot (Olivine)
Olivine, (Mg,Fe)2SiO4
Mineral
River/Stream Pebble
Clast / Detrital Grain / Rounded Sedimentary Particle (Compositionally variable, commonly Quartz, Feldspar, Chert, or other resistant rock fragments)
Mineral, specifically a rock fragment
Obsidian with Spherulitic Devitrification (Snowflake Obsidian/Mahogany related)
Volcanic Glass (70% or more SiO2)
igneous
Marble
Recrystallized Calcite / Dolomite (CaCO3)
metamorphic
River Pebble (Quartz/Jasper)
Silicon Dioxide (SiO2)
sedimentary
Green Apophyllite and Stilbite on Quartz Cluster
Apophyllite-(K) (KCa4(Si8O20)(F,OH)·8H2O), Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O), Quartz (SiO2)
Mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Feldspar Rich Granite with Limonite Staining
K-Feldspar Granite (KAlSi3O8)
igneous
Marble
Recrystallized Calcite (CaCO3)
metamorphic
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Rainbow Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
sedimentary
Chert Pebble (Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Greywacke (River Slikkenstone)
Greywacke (Impure Sandstone)
sedimentary
Milky Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Fluorite (likely Green Fluorite variant)
Calcium Fluoride (CaF2)
mineral
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
igneous
Basalt with Granite Inclusions (Xenoliths)
Mafic igneous rock (Basalt) with Sialic minerals
igneous
Quartz (likely a clear or rock crystal variety)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica/Amphibole)
metamorphic
Chalk
Micrite (primarily Calcium Carbonate, CaCO3)
sedimentary
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Yellow Quartzite Pebble
Quartzite (primarily Silicon Dioxide - SiO2)
metamorphic
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Granite
Phaneritic Felsic Igneous Rock (Main minerals: SiO2, KAlSi3O8, NaAlSi3O8)
igneous
Gneiss (specifically Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Geode (Unopened)
Silicon Dioxide (SiO2) in sedimentary vugs
sedimentary
Granite Pebble (Salt and Pepper Granite)
Felsic Intrusive Igneous Rock (Granite)
igneous
Sandstone Geode (Unbroken)
Siliciclastic sedimentary rock (primarily Quartz)
sedimentary
Quartz-veined Siltstone
Siltstone with Quartz (SiO2) veins
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Basalt
Basalt (Mafic Extrusive Igneous Rock)
igneous
Rose Quartz
Rose Quartz (SiO2)
Mineral
Milk Quartz (Common White Quartz)
Quartz (Silicon Dioxide, SiO2)
mineral
Banded Gneiss
Gneiss (pronounced "nice")
Metamorphic Rock
Granodiorite with Quartz Veining
Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins
igneous
Blue Quartzite
Quartzite (specifically a variety enriched with blue-coloring minerals)
Metamorphic Rock