Unakite
Epidotized Granite
metamorphic
Category
Igneous Rock
Browse igneous rock specimens identified by the Rock Identifier community.
Pink Quartzite
Quartzite (SiO2 with minor iron oxide impurities)
metamorphic
Conglomerate
Conglomerate rock
sedimentary
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Sandstone Cobble
Clastic Sedimentary (Sandstone)
sedimentary
Chert / Chalcedony (likely carnelian or flint variety)
Silicon Dioxide (SiO2)
sedimentary
Not a geological specimen
N/A (man-made object)
N/A
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
mineral
Ferrochrome Slag
Anthropogenic silicate/oxide glass (Complex silicate matrix with Cr-Fe-Si inclusions)
Industrial byproduct (often confused with igneous rocks or meteorites)
Sandstone (Ferruginous)
Arenite (Siliclastic Sedimentary Rock)
sedimentary
Conglomerate
Conglomerate rock
sedimentary
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Mineral
Shale
Argillaceous Rock
sedimentary
Agate Geode
Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety
Mineral
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
mineral
Schist
Schist
metamorphic
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
mineral
Yellow Quartzite
Quartzite (SiO2 with iron oxide inclusions)
metamorphic
Puddingstone (Gowganda Tillite/Jasper Conglomerate)
Jasper Conglomerate (SiO2 primary composition)
sedimentary
Druzy Quartz on Chalcedony Matrix
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Crystalline)
Silicon Dioxide (SiO2)
mineral
Quartz Geode
Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell
sedimentary
Schist
Mica Schist (Medium-grade Metamorphic Rock)
Metamorphic
Garnet Schist
Almandine-Muscovite Schist
metamorphic
Limonite (after Pyrite Pseudomorph)
Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)
mineral
Quartz Veined Rock (Likely Graywacke or Quartzite)
Silicon Dioxide (SiO2) veins in Metasedimentary matrix
metamorphic
Agate
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Agate (Common Chalcedony)
Silicon Dioxide (SiO2)
mineral
Asphalt Chunk (with aggregate)
Bituminous concrete / Anthropogenic conglomerate
sedimentary (anthropogenic/man-made conglomerate)
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Schist
Schist (various mineralogical compositions including mica, chlorite, talc, etc.)
Metamorphic
Quartz
Quartz (SiO2, Silicon Dioxide)
Mineral
Dearest Jewelry (Multigemstone)
Combination of Diamond (C), Emerald (Be3Al2Si6O18), Amethyst/Rock Crystal (SiO2), Ruby (Al2O3), Emerald (Be3Al2Si6O18), Sapphire (Al2O3), and Topaz (Al2SiO4(F,OH)2)
Mineral
Lapis Lazuli (blue bead) and Moss Agate (green heart)
Lapis Lazuli (lazurite-based rock) and Moss Agate (SiO2 with manganese/iron inclusions)
metamorphic (Lapis) and sedimentary/igneous assoc. (Moss Agate)
Agate Geode with Quartz Druzy
Chalcedony (SiO2) and Quartz (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
mineral
Banded Sandstone
Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)
sedimentary
Chert (Arrowhead)
Chert (primarily Microcrystalline Silica, SiO2)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2) within a geode
mineral
Serpentine
Antigorite, Lizardite, or Chrysotile (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
metamorphic
Metaconglomerate
Protolith: Conglomerate (comprising SiO2, Al2O3, etc.)
metamorphic
White Jade (Nephrite)
Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2
Mineral