Gneiss
Gneiss (High-grade regional metamorphic rock)
metamorphic
Category
Mineral Like Byproduct (Often Mistaken For Igneous Rock Or Meteorite)
Browse mineral like byproduct (often mistaken for igneous rock or meteorite) specimens identified by the Rock Identifier community.
Turquoise and Hematite
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)
mineral
Quartz (Milky or Cloudy variety)
Quartz (Silicon Dioxide, SiO2)
mineral
Rose Quartz
Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Quartz (variety of colors)
SiO2 (Silicon Dioxide)
Mineral
Sodalite
Sodium aluminum silicate chloride (Na8(Al6Si6O24)Cl2)
mineral
Emerald in Matrix
Emerald (Beryllium Aluminum Silicate), Be3Al2(SiO3)6
mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
Igneous
Dendritic Agate (or Dendritic Opal)
SiO2 (for Agate), SiO2·nH2O (for Opal)
Mineral
Epidote in Quartz
Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) in Milky Quartz (SiO2)
metamorphic
Clear Quartz (Carved Dragon)
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz-veined Mudstone or Argillite
SiO2 (Quartz) in Siltstone/Mudstone matrix
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
igneous
Chert (also known as Flint or Common Chalcedony)
Cryptocrystalline Silica (SiO2)
sedimentary
Granitic Pegmatite with Schorl Tourmaline
Granitic Pegmatite (Schorl: NaFe3Al6(BO3)3Si6O18(OH)4)
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Labradorite (Polished Crystal Point)
Labradorite (a calcium-enriched feldspar mineral), (Ca, Na)(Al, Si)4O8
mineral
Crushed Stone (Basalt/Gabbro)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
mineral
Granite
Phaneritic Felsic Igneous Rock
igneous
Basalt (Crushed Stone Aggregate)
Mafic Volcanic Basalt (Major Minerals: Plagioclase Feldspar, Pyroxene, Olivine)
igneous
Pyrite
Iron Sulfide (FeS2)
mineral
Diorite (with Iron Staining)
Phaneritic Intermediate Igneous Rock
igneous
Epidosite
Epidosite (predominantly Epidote {Ca2Al2Fe3+Si3O12(OH)} and Quartz {SiO2})
metamorphic
Garnet (likely Almandine or a blend)
Garnet group: X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+. Given the dark, somewhat reddish-brown appearance in the image, it's likely Almandine (Fe3Al2(SiO4)3) or a mix with other iron-rich garnets.
Mineral
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
igneous
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Chalcopyrite
Chalcopyrite (CuFeS2)
mineral
Serpentinite
Serpentinite ((Mg,Fe,Ni,Al)3Si2O5(OH)4)
metamorphic
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartz (Riverstone / Cobble)
Silicon Dioxide (SiO2)
mineral
Vesicular Basalt with Oxidation
Scoriaceous Olivine Basalt (Mafic volcanic rock)
igneous
Schist
Mica Schist
metamorphic
Red Sandstone
Arenite (with Iron Oxide cement)
sedimentary
Agate Geode
Banded Chalcedony (Silicon Dioxide, SiO2) with Quartz crystals
mineral
Limonite Concretion (Ironstone)
Limonite / Goethite (FeO(OH)·nH2O)
sedimentary
Drill Core Samples (Varied Lithology)
Multi-lithological core samples (containing potential granite, marble, and phyllite/schist sequence)
igneous, sedimentary, and metamorphic
Sandstone
Arenite (often composed of Quartz, SiO2)
sedimentary
Sandstone or Mudstone
Sedimentary Rock (Sandstone/Mudstone)
sedimentary