Ferruginous Sandstone (Ironstone)
Ferruginous Sandstone / Limonite-cemented Quartz Sandstone
Category
Browse sedimentary like (industrial composite) specimens identified by the Rock Identifier community.
Ferruginous Sandstone (Ironstone)
Ferruginous Sandstone / Limonite-cemented Quartz Sandstone
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2)
Howlite
Howlite, Ca₂B₅SiO₉(OH)₅
Sandstone (with cross-bedding)
Arenite (composed primarily of Quartz: SiO2)
Tumbled picture jasper
Microcrystalline quartz (SiO₂), commonly with iron-oxide and clay inclusions
Blue Calcite
Calcium Carbonate (CaCO3)
Yellow Calcite
Calcium Carbonate (CaCO3)
Red Sandstone
Arenite (with Iron Oxide / Hematite), Formula: SiO2 (Quartz) + Fe2O3 (Hematite coating)
Granitic Sand
Detrital sediment (predominantly Quartz, Feldspar, and Mica)
Emerald in Matrix
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Marble (Carrara style)
Recrystallized Calcite-rich Metamorphic Rock (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Smoky Quartz with Chert
Silicon Dioxide (SiO2)
Quartz (Milky/Chalcedony variety)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper/Flint)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Sandstone (likely Iron-rich or Arkosic)
Arenite (SiO2 with FeO(OH) or Fe2O3 staining)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Chalcedony (Chert/Flint)
Silicon Dioxide (SiO2)
Mica Schist
Mica Schist (Silicate rock)
Chert (and Jasper/Chalcedony variety)
Microcrystalline Quartz (SiO2)
Kaolinite Claystone
Al2Si2O5(OH)4 (Kaolinite)
Chert
Chert (Microcrystalline Quartz, SiO2)
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
Chert (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Small tumbled quartz-like pebble
Likely quartz (SiO₂), possibly iron-stained chalcedony or feldspar
Beryl (likely Pink/Morganite variety)
Beryllium aluminum silicate (Be3Al2Si6O18)
Likely black beach pebble
Undetermined; possibly basalt, chert, or dark slate
Dyed Chalcedony (Agate)
Silicon Dioxide (SiO2) with artificial pigment
Polished fossil coral
Fossilized coral, commonly agatized coral (silica replacing CaCO₃)
Jasper (Red Jasper)
Silicon Dioxide (SiO₂)
Quartz Geode
Crystalline Silicon Dioxide (SiO2)
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Chert (specifically Flint or Novaculite variant)
Chert (Microcrystalline Quartz, SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Gneiss (specifically Micaceous Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
Sandstone (Ferruginous)
Arenite (with Iron Oxide cement)
Raw Corundum (Sapphire/Ruby variant)
Aluminum oxide (Al2O3)
Hag Stone
Flint / Chert / Limestone concretion with a natural hole
Quartz Geode
Silicon Dioxide (SiO2)
Fluorite (Green Fluorite)
Calcium Fluoride (CaF2)
Yellow Chert (Chert/Jasper)
Silicon Dioxide (SiO2)