Gemstone Ring
Various (Likely Glass, Cubic Zirconia, or assorted semi-precious stones)
gemstone
Category
Mineral Health
Browse mineral health specimens identified by the Rock Identifier community.
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Amethyst
Purple variety of quartz; silicon dioxide (SiO₂)
gemstone
Amethyst beads
Amethyst, purple quartz (SiO₂)
gemstone
Mixed Mineral Assortment (Pyrite, Kyanite, Agate, Jasper)
FeS2 (Pyrite), Al2SiO5 (Kyanite), SiO2 (Agate/Jasper)
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Weathered iron-rich metamorphic rock, possibly schist or metabasalt
Provisional identification: chlorite–quartz–feldspar schist or altered basalt; exact mineralogy requires testing
metamorphic
Rounded, banded metamorphic cobble
Likely gneiss or foliated quartz-rich metamorphic rock; exact identification is uncertain from the photograph.
metamorphic
Quartz-rich pegmatite with mica and dark inclusions
Pegmatite; chiefly quartz (SiO₂), with feldspar and biotite/tourmaline inclusions
igneous
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Chevron Amethyst
Silicon Dioxide (Quartz variety), SiO2
mineral
Amethyst
Silicon Dioxide (SiO2), Quartz variety
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz with Tourmaline
Silicon Dioxide with complex boro-silicate (Quartz: SiO2)
mineral
Moqui Marble
Hematite-Goethite Concretion
mineral
Quartz Geode Fragment
Silicon Dioxide (SiO2)
sedimentary
Lepidolite in Quartz
K(Li,Al)3(Si,Al)4O10(F,OH)2 / SiO2
mineral
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
sedimentary
Polished orbicular jasper (likely ocean jasper)
Silicified volcanic rock; microcrystalline quartz/chalcedony (SiO₂) with iron oxides and altered volcanic minerals
metamorphic
Polished copper-bearing mineral specimen, likely malachite-rich copper ore
Malachite, Cu₂CO₃(OH)₂, possibly mixed with chrysocolla or limonite
mineral
Small tumbled orange-brown mineral fragment
Indeterminate; possibly iron-stained quartz, carnelian, or orange calcite
mineral
Herkimer Diamond
Double-terminated Quartz (Silicon Dioxide, SiO2)
mineral
Granite
Granite, a coarse-grained felsic intrusive igneous rock composed chiefly of quartz, feldspar, and mica
igneous
Greenstone / altered basalt (probable)
Chlorite–epidote–actinolite aggregate; commonly metabasalt (greenstone)
metamorphic
Carved serpentine wing sculpture
Serpentine-group rock, chiefly antigorite/lizardite: Mg3Si2O5(OH)4
metamorphic
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Polished blue-gray mineral specimen, likely galena-bearing ore
Galena (PbS), possibly mixed with quartz/calcite and secondary copper minerals
mineral
Quartz pebble
Silicon dioxide (SiO2)
mineral
Possible fossilized bone fragment
Indeterminate fossil bone; no species can be identified from this image
fossil
Conglomerate (or Breccia / Porphyry)
Clastic Sedimentary Rock (Conglomerate / Sandstone)
sedimentary
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Iron-stained milky quartz
Quartz (SiO₂), with iron-oxide staining
mineral
Iron-stained milky quartz pebble
Quartz (SiO₂), commonly with iron-oxide staining
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Limonite Concretion
Goethite/Limonite concretion (FeO(OH)·nH2O)
sedimentary
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Biotite-rich gneiss (probable)
Foliated quartz–feldspar–biotite gneiss; composition commonly includes quartz (SiO₂), feldspar, and biotite mica
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Limonite Geode / Ironstone Concretion
Hydrated iron oxide-hydroxide (FeO(OH)·n H2O)
sedimentary