Moqui Marble (Ironstone Concretion)
Goethite/Hematite Concretion (Fe2O3 / FeO(OH))
sedimentary
Category
Sedimentary Rock (Specifically A Concretion Or Possibly A Geode)
Browse sedimentary rock (specifically a concretion or possibly a geode) specimens identified by the Rock Identifier community.
Ironstone Concretion (Moqui Marble)
Hematite/Goethite Concretion (Fe2O3 / FeO(OH))
sedimentary
Amethyst
Silicon Dioxide (SiO2) with traces of Iron and Manganese
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Mineral
Celestine (Celestite)
Strontium sulfate (SrSO4)
mineral
Quartz Druze
Silicon Dioxide (SiO2)
mineral
Desert Rose
Gypsum (variety Selenite) - CaSO4·2H2O
mineral
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Beaded Jewelry (Assorted Gemstones)
Various minerals, including but not limited to Quartz (SiO2), Garnet (X3Y2(SiO4)3), Jade (Na(Al,Fe)Si2O6), Amethyst (SiO2),等の多様な組み合わせ
Mineral, Jewelry
Pink Granite
Granite (Phaneritic igneous rock)
igneous
Coarse Sand Grain / Lithic Fragment
Clastic Sediment (Lithic fragment or Quartz/Feldspar grain)
sedimentary
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Limestone with Weathering Rind
Calcium Carbonate (CaCO3) - Bioclastic or Micritic Limestone
sedimentary
Mica (Biotite and Muscovite) in Matrix
Potassium aluminum silicate with iron/magnesium (KAl2(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(F,OH)2)
igneous
Chert (Quartzite-rich River Pebble)
Silicon Dioxide (SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone or Limonite (FeO(OH)·nH2O)
sedimentary
Gneiss (specifically a Granitic Gneiss)
Gneiss (Composition: Quartz, Feldspar, Mica)
metamorphic
Amethyst (Quartz)
Amethyst (SiO2 with iron impurities)
mineral
Red Quartzite Slipper Stone
Quartzite (SiO2)
metamorphic
Sandstone with Concretions / Liesegang Rings
Arenite with iron oxide banding
sedimentary
Chert / Flint Nodules in Limestone
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
mineral
Dyed Quartz Geode
Silicon Dioxide (SiO2) with artificial pigment
mineral
Fossiliferous Limestone
Calcite-rich Sedimentary Rock (CaCO3)
sedimentary
Sandstone
Arenite (primarily Quartz, SiO2)
sedimentary
Blue Dyed Agate Geode
Chalcedony (cryptocrystalline Quartz), SiO2
mineral
River Rock
Sedimentary Rock (various compositions)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Pink Granite
Granite (Felsic Plutonic Rock)
igneous
Chalcedony
Chalcedony (SiO₂)
Mineral
Metal Alloy (Likely Pewter or Sterling Silver)
Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).
Man-made material (metal)
Quartzite Pebble (River Rock)
Metamorphic Quartzite (predominantly SiO2)
metamorphic
Amygdaloidal Basalt
Amygdaloidal Basalt
igneous
Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities
mineral
Pink Granite
Granite (Felsic Plutonic Rock)
igneous
Yellow Jasper
Silicon Dioxide (SiO2)
sedimentary
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Carnelian
Carnelian (Silicon Dioxide: SiO2 with Iron Oxide impurities)
mineral
Celestite (Celestine)
Strontium sulfate (SrSO4)
mineral