Milky Quartz with Iron Staining and Matrix
Silicon Dioxide (SiO2)
Category
Browse mineral (native element alloy) specimens identified by the Rock Identifier community.
Milky Quartz with Iron Staining and Matrix
Silicon Dioxide (SiO2)
Pyrite in Quartzite/Graphite Matrix
Iron Sulfide (FeS2)
Ironstone with Pyrite
Ferruginous Sandstone (Fe2O3) with minor Sulfide minerals (FeS2)
Pink Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
White Howlite
Howlite (Calcium borosilicate hydroxide, Ca2B5SiO9(OH)5)
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Diorite
Diorite (Intermediate intrusive igneous rock)
Red Sandstone
Arenite (with Iron Oxide / Hematite cementation)
Greenstone / Diabase Porphyry
Porphyritic Diabase (Micro-gabbro)
Fossilized Sand Tiger Shark Tooth
Carcharias taurus / Striatolamia macrota (mineralized as Hydroxylapatite/Francolite)
Pink Opal / Peruvian Opal
Hydrated amorphous silicon dioxide (SiO2·nH2O)
Concretion
Various mineral compositions, typically carbonate or iron oxide cemented sediment
Quartz / Quartzite
Silicon Dioxide (SiO2)
Jasper (Iron-stained Quartzite/Chert)
Silicon Dioxide (SiO2) with iron oxide inclusions
Pearl (nacre)
Calcium Carbonate (mostly CaCO3 as Aragonite) and Conchiolin
Fluorite
Calcium Fluoride (CaF2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Concretion or Geode (unbroken)
Varied (depending on mineral composition and cementing agent). For quartz-lined geodes, the scientific name of the dominant mineral would be Quartz (SiO2). For calcite-lined geodes, Calcite (CaCO3). Concretions are often composed of cryptocrystalline quartz (chert), calcite, or iron oxides.
Ferruginous Sandstone (Gozzan/Ironstone)
Arenite with Limonite/Goethite cement (FeO(OH)·nH2O)
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Epidote
Epidote - Ca2(Al,Fe)3(SiO4)3(OH)
Pyrite
Iron Disulfide (FeS2)
Sandstone
Arenite (composed mainly of SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Sandstone
Sandstone (Sedimentary rock composed of silicate grains)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Sandstone
Arenite (SiO2 predominantly)
Amber
Succinite (fossilized tree resin), C10H16O
Pink Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Gneiss
Gneiss
Quartzite
Quartzite (SiO2)
Quartz Druze (Crystalline Quartz)
Silicon Dioxide (SiO2)
Clear Quartz
SiO2 (Silicon Dioxide)
Yellow Quartz or Citrine
Silicon Dioxide (SiO2)
Amethyst (Chevron Amethyst)
Amethystine Quartz (SiO2)
Amethyst or Smoky Quartz Geode Slice
Crystalline Silicon Dioxide (SiO2) with iron impurities
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Citrine
Silicon Dioxide (SiO2) with iron impurities
Clear Quartz
Silicon Dioxide (SiO2)