Chert (Commonly known as Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Category
Sedimentary (Primary) With Artificial Modification
Browse sedimentary (primary) with artificial modification specimens identified by the Rock Identifier community.
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
metamorphic (man-made / anthropic)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (containing Orbicular/Agate patterns)
Microcrystalline Quartz (SiO2)
sedimentary
Amber Flint (Chert)
Cryptocrystalline Quartz (Silicon Dioxide, SiO2)
sedimentary
Jasper with Quartz inclusions
Silicon Dioxide (SiO2) - Microcrystalline Chalcedony
sedimentary
Chert (specifically Black Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Blue-Gray Chert)
Microcrystalline quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Red Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Geode with Iron-Stained Quartz/Calcite
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) in Sedimentary Matrix
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Magnetite (Iron Ore)
Magnetite (Fe3O4)
mineral
![Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral](https://media.rockidentification.com/bd94961c-533a-4ed4-b8e1-773f9b478c18-thumbnail.jpg)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Asphalt Concrete (Bituminous Concrete)
Bituminous aggregate
sedimentary
Howlite
Howlite (Calcium borosilicate hydroxide: Ca2B5SiO9(OH)5)
mineral
Agate (specifically, multi-colored or pastel-dyed agate)
Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).
Mineral
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Man-made Object/Uncertain Mineral
Thunderegg (Ate Agate/Jasper Geode)
Silicon Dioxide (SiO2) within Rhyolite/Perlite matrix
sedimentary/igneous intermediary
Bauxite
Bauxite (Al2O3·nH2O)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Zebra Jasper
Tumbled Opaque Chalcedony (SiO2)
sedimentary
Yellow Jasper
SiO2 (Silicon Dioxide)
sedimentary
Sandstone Concretion
Ferruginous Sandstone Concretion (Primarily SiO2 with Iron Oxide cement)
sedimentary
Bauxite
Bauxite (Mixture of Hydrous Aluminum Oxides)
sedimentary
Bauxite / Iron-rich Laterite
Laterite (principally Al(OH)3, Fe2O3, and SiO2)
sedimentary
Banded Iron Formation (BIF)
Banded Iron Formation (SiO2 + Fe2O3/Fe3O4)
sedimentary
Granite Cobble
Phaneritic Felsic Igneous Rock (Granite)
igneous
Peridot (likely, given the color and bead form)
Olivine, variety Peridot (Mg,Fe)2SiO4
Mineral
Hematite
Iron(III) oxide (Fe2O3)
Mineral
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz vein in Host Rock
Crystalline Silicon Dioxide (SiO2) in Lithic Matrix
metamorphic
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Quartz (Milky/Common variant)
Silicon Dioxide (SiO2)
mineral
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
mineral
Conglomerate
Conglomerate (SiO2 primary clasts with lithic matrix)
sedimentary
Chert (varietal: Flint or River Pebble)
Silicon Dioxide (SiO₂)
sedimentary
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary