Corundum
Corundum (Al2O3)
Category
Browse sedimentary (alluvial deposit) specimens identified by the Rock Identifier community.
Corundum
Corundum (Al2O3)
Picture Jasper
Silicon Dioxide (SiO2) with impurities
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Quartz Geode (Cracked)
Quartz (Silicon Dioxide, SiO2)
Celestite (Celestine)
Strontium sulfate (SrSO4)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminium phosphate)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert / Chalcedony
Silicon Dioxide (SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles
Mixed gemstones (primarily Silicon Dioxide - SiO2)
Chert / Jasper
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Chalcedony/Agate variety)
Microcrystalline Quartz (SiO2)
Red Jasper
Jasper (Silicon Dioxide) - SiO2
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Chert (Yellow Jasper variant)
Microcrystalline quartz (SiO2)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Pyrite with Calcite
Iron Disulfide (FeS2) with Calcium Carbonate (CaCO3)
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
Yellow Jasper (Chert)
Silicon Dioxide (SiO2) with iron inclusions
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Mookaite Jasper
Silicon Dioxide (SiO2) - Radiolarite
Agate (or Chalcedony)
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2)
Plume Agate
Silicon Dioxide (SiO2)
Selenite (Satin Spar Gypsum)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Hematite
Iron(III) oxide (Fe2O3)
Shale
Fissile mudstone (rich in clay minerals and quartz)
Halite
Halite (NaCl)
River Rock (likely Siltstone or fine-grained Sandstone)
Clastic Sedimentary Rock
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Mookaite Jasper
Silicified radiolarite (SiO2)
Limonite (Iron Stone)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
Agate Geode
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2)
Shale with Vein Infillings
Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)