Gneiss
Gneiss
metamorphic
Category
Mineral Health
Browse mineral health specimens identified by the Rock Identifier community.
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Pyrite
Iron Disulfide (FeS2)
mineral
Fluorite (left), Sodalite (middle), Dumortierite/Tumbled Quartzite (right)
Calcium Fluoride (CaF2), Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2), Aluminum Borosilicate (Al7(BO3)(SiO4)3O3)
mineral
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Quartz Geode
Silicon dioxide (SiO2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Granodiorite (or Granite) Pebble
Phaneritic Felsic Igneous Pebble
igneous
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
mineral
Granite
Granite
igneous
Jadeite and Mixed Gemstones (Ruby, Sapphire, Emerald)
Jadeite (NaAlSi2O6), Corundum (Al2O3), Beryl (Be3Al2(Si6O18))
mineral
Sandstone Concretion with Quartz Center
Sedimentary Clastic Rock (SiO2 matrix with Quartz core)
sedimentary
Epidosite
Epidosite (Metasomatic rock consisting mainly of Epidote and Quartz)
metamorphic
Emerald in Host Rock
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Citrine
SiO2 (Silicon Dioxide)
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
igneous
Greenstone (Amygdaloidal Basalt)
Amygdaloidal Basalt (frequently composed of Plagioclase Feldspar, Pyroxene, and Olivine with Chlorite inclusions)
igneous
Fluorite (Rainbow or Multi-colored Fluorite)
Fluorite (Calcium Fluoride - CaF2)
mineral
Turquoise and Hematite
CuAl6(PO4)4(OH)8·4H2O (Turquoise) and Fe2O3 (Hematite)
mineral
Red Sandstone (Iron-rich)
Ferruginous Sandstone (SiO2 with Iron Oxides)
sedimentary
Quartz-veined Sedimentary Rock
Hydrothermally veined Clastic Sedimentary Rock (SiO2 veins in Matrix)
sedimentary
Sandstone (likely with Quartz Veining)
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite (lithic or quartz sandstone)
sedimentary
Note: Item is not a geological specimen
Homo sapiens (Dermal Appendage: Pilus)
Organic / Biological
Amygdaloidal Basalt
Vesicular-Amygdaloidal Basalt (Mafic Extrusive)
igneous
Sandstone (likely Quartzose Sandstone pebble)
Arenite (primarily SiO2)
sedimentary
Malachite
Malachite (Copper Carbonate Hydroxide, Cu2CO3(OH)2)
mineral
Educational Geologic Collection
Mixed Mineral and Rock Collection (Various compositions)
mineral
Milky Quartz with Mineral Inclusions
Quartz (Silicon Dioxide - SiO2)
mineral
Flesh-colored Quartz Mineral
SiO2 (Silicon Dioxide) with Iron Impurities
mineral
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
sedimentary
Slate
Foliated Metamorphic Rock (primarily composed of quartz, illite, chlorite, and micas)
metamorphic
Granite
Granite
igneous
![Limonite Geode (Ironstone Concretion) (Limonite [FeO(OH)·nH2O] with possible Quartz or Calcite interior) — sedimentary](https://media.rock.id/23e3b366-c658-41d4-99f3-53fdaa23a555-thumbnail.jpg)
Limonite Geode (Ironstone Concretion)
Limonite [FeO(OH)·nH2O] with possible Quartz or Calcite interior
sedimentary
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Turquoise in Matrix
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
mineral
Limonite Concretion (Ironstone)
Limonite (Hydrated Iron(III) Oxide-Hydroxide, FeO(OH)·nH2O)
sedimentary
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated Iron Oxide)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Limonite (vibrant yellowish-brown iron oxide)
Limonite (FeO(OH)·nH2O)
mineral
Limonite / Ironstone
Hydrated ferric oxide (FeO(OH)·nH2O)
mineral
Lapis Lazuli
Lapis Lazuli (Complex silicate rock containing Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)
metamorphic
Bauxite
AlOx(OH)3-2x (mixture of Gibbsite, Boehmite, and Diaspore)
sedimentary