Tumbled milky quartz pebble
Quartz, silicon dioxide (SiO₂), microcrystalline to coarsely crystalline variety
mineral
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
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Pyrite-bearing schist (likely mica schist)
Muscovite–quartz schist with disseminated pyrite (FeS₂)
metamorphic
Red jasper (likely rough jasper/chert)
Microcrystalline quartz (SiO₂), commonly colored by iron oxides
mineral
Red Jasper (possibly Petrified Wood)
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary (secondary formation)
Fossilized Shark Tooth
Lamniformes (order) fossil
fossil
Petrified Wood
Petrified Wood (Silicified Wood)
fossil
Banded Siltstone
Siltstone (primarily SiO2 with clay minerals)
sedimentary
Sandstone with Trace Fossils
Arenite with Ichnofossils
sedimentary
River Rock
Polished Siliceous Rock / Quartzite Pebble
sedimentary
Banded Chert
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Banded Chert Pebble
Silicon Dioxide (SiO2)
sedimentary
Banded Chert / Sandstone Pebble
Microcrystalline Quartz (SiO2) / Silicified Sandstone
sedimentary
Belemnite Fossil
Belemnitida (Order of extinct cephalopods)
sedimentary
Glauconitic Sandstone
Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2 in Quartz Sandstone
sedimentary
Banded chert or silicified limestone nodule
Microcrystalline quartz (SiO₂), possibly replacing carbonate fossils
sedimentary
Red Jasper with Quartz
Silicon Dioxide (SiO2) with Hematite impurities
sedimentary
Jasper
Jasper (Silica-rich Microcrystalline Quartz, SiO2)
sedimentary
Gastropod Fossil (Snail)
Gastropoda (Internal mold/Steinkern)
sedimentary
Ironstone Concretion (Siderite Nodules)
Siderite (FeCO3) in Mudstone or Sandstone matrix
sedimentary
Iron-rich chert or jasper
Microcrystalline quartz (SiO₂), colored by hematite/goethite inclusions
sedimentary
Ironstone Concretion
Ferruginous Sandstone / Hematite-rich Concretion
sedimentary
Ironstone Nodules / Siderite Concretion
Siderite (FeCO3) / Ferruginous Septarian Concretion
sedimentary
Ironstone Concretion (Limonite/Goethite)
Iron oxide concretion (contains FeO(OH)·nH2O)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
sedimentary
Sandstone Concretion with Fossil Wood
Ferruginous Sandstone Concretion (SiO2 with Fe2O3 cement)
sedimentary
Kambaba Jasper
Stromatolite (Fossilized Algae)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
fossil
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Yellow jasper (likely ocean jasper or brecciated jasper)
Jasper, microcrystalline quartz (SiO₂) with iron-oxide staining and dark mineral veins
mineral
Red Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
mineral
Red Jasper
Silicon Dioxide (SiO2)
sedimentary
Sandstone (Graywacke)
Clastic Sedimentary Rock (Lithic Sandstone)
sedimentary
Ferruginous Sandstone
Clastic Sedimentary Rock (Iron-rich)
sedimentary
Concretion
Septarian concretion (likely containing Calcite or Siderite)
sedimentary
Common Gravel / Pebble
Lithified rock fragment / Detrital sediment
sedimentary
Rounded granitic cobble
Granite or granitic gneiss; primarily quartz, feldspar, and mica
igneous
Fossils in Limestone (Crinoid / Marine Invertebrate Fossil)
Fossiliferous Limestone (containing Crinoidea / Brachiopoda)
fossil
Sandstone
Arenite
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Mookaite (Mookaite Jasper)
Silicified Radiolarite (SiO2 with iron oxides)
sedimentary