Red Sandstone
Arenite (primarily SiO2 with Fe2O3)
sedimentary
Category
Sedimentary Rock Or Mineral (Depending On Origin And Purity)
Browse sedimentary rock or mineral (depending on origin and purity) specimens identified by the Rock Identifier community.
Learn about Sedimentary Rock Or Mineral (Depending On Origin And Purity) in the encyclopedia
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Gold Nugget
Native Gold (Au)
mineral
Sandstone Concretion
Sedimentary Concretion (Quartz sand bound by mineral cement)
sedimentary
Sandstone
Clastic sedimentary rock
sedimentary
Diamond
Diamond (Pure Carbon, C)
mineral
Banded Metamorphic Rock
Gneiss or Schist
metamorphic
Sandstone (Banded)
Sedimentary Clastic Rock
sedimentary
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (Lithic Sandstone)
sedimentary
Sandstone
Clastic Sedimentary Rock
sedimentary
Ferruginous Sandstone (with possible trace fossils)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)
sedimentary
Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
sedimentary
Green glassy mineral fragment, likely peridot or green fluorite
Possibly olivine (forsterite–fayalite series), Mg₂SiO₄, or fluorite, CaF₂; exact identification requires testing
gemstone
Sandstone
Sedimentary Clastic Rock
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Turquoise-look beads, likely dyed howlite or magnesite
Often dyed CaCO₃ (howlite/magnesite), rather than natural turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O
mineral
Mixed rock and mineral specimen collection
Multiple species, likely quartz (SiO₂), calcite (CaCO₃), feldspar, chert, and assorted volcanic/sedimentary rocks
mineral
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Sandstone (Quartzose)
Arenite (SiO2 based)
sedimentary
Dyed turquoise-colored howlite or magnesite (likely imitation turquoise)
Howlite: Ca₂B₅SiO₉(OH)₅; magnesite: MgCO₃
mineral
Sandstone (Ferruginous)
Arenite with Iron-oxide inclusions (SiO2 primarily)
sedimentary
Geode (Unopened)
Silica-rich Concretion (SiO2)
sedimentary
Sandstone (with Iron Staining)
Arenite (Silicon Dioxide, SiO2, often with iron oxides like Limonite)
sedimentary
Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
mineral
Sandstone
Sedimentary Clastic Rock
sedimentary
Sandstone Cobble
Arenite (primarily Quartz Arenite)
sedimentary
Sandstone
Sedimentary Rock (Quartz Arenite)
sedimentary
Gneiss
Gneiss
metamorphic
Sandstone
Sedimentary Rock (Quartzose Sandstone)
sedimentary
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Mineral
Fluorite on Matrix
Calcium Fluoride (CaF2)
mineral
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Sandstone
Clastic Sedimentary Rock
sedimentary
Brown chert (flint)
Microcrystalline quartz (SiO₂), commonly called chert; the specimen may be iron-stained
sedimentary
Sandstone
Arenite (composed primarily of Quartz, SiO2)
sedimentary
Zircon
Zircon (Zirconium Silicate - ZrSiO4)
mineral
Sandstone
Clastic Sedimentary Rock
sedimentary
Faceted citrine-colored gemstone
Likely citrine (quartz, SiO₂); possibly yellow glass or synthetic gem
gemstone
Druzy Quartz on Chalcedony Matrix
Silicon Dioxide (SiO2)
mineral
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Metamorphic Rock
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral