Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Category
Browse sedimentary (alluvial deposit) specimens identified by the Rock Identifier community.
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Hematite
Hematite (Fe2O3)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
White Howlite
Howlite (Calcium borosilicate hydroxide, Ca2B5SiO9(OH)5)
Crinoid Fossil in Limestone
Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)
Turquoise (possible Dyed Howlite or Magnesite imitation)
CuAl6(PO4)4(OH)8·4H2O (Turquoise)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Dyed Agate (Tumbled)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Aragonite Star Cluster (or Aragonite Sputnik)
Aragonite (Orthorhombic Calcium Carbonate, CaCO3)
Coal (most likely Bituminous or Anthracite)
Coal (primarily composed of carbon with varying amounts of other elements)
Quartz Vein in Sedimentary Matrix
Silicon Dioxide (SiO2) with host rock
Fossiliferous Limestone
Calcite (CaCO3) with Bioclastic inclusions
Quartz Geode
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Caliche (also known as hardpan, calcrete, kankar)
Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.
Puddingstone (Conglomerate)
Conglomerate (clastic sedimentary rock)
Black Jasper (Black Stone / River Pebble)
Silicon Dioxide (SiO₂), Opaque variety of Chalcedony
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with impurities of Iron Oxide
Fancy Jasper (Multicolor Agate/Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Coquina Limestone (Fossiliferous Limestone)
Calcareous bioclastic sedimentary rock (CaCO3)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Mookaite Jasper
Silicified Porcellanite (SiO2 with impurities)
Sandstone
Arenite
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (SiO2 + various cementing minerals)
Chert (varieties: Flint or Chalcedony)
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide impurities (Hematite)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite
Siltstone with iron staining
Siltstone (primarily SiO2 with FeO(OH) coatings)
Septarian Nodule
Septarian Concretion (Calcium Carbonate/Aragonite/Calcite)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Chert / Pink Chert
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Coquina / Fossiliferous Limestone
Coquina (composed primarily of Calcium Carbonate / CaCO3)
Siltstone
Siltstone
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Mookaite Jasper
Silicified Radiolarite (SiO2)
Bauxite (Laterite Clay)
Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))
Moqui Marble (Concretion)
Iron Oxide Concretion (Hematite-cemented Sandstone)