Mother of Pearl and Onyx
Aragonite (Mother of Pearl) and Chalcedony (Onyx)
Category
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Mother of Pearl and Onyx
Aragonite (Mother of Pearl) and Chalcedony (Onyx)
Tumbled sandstone pebble
Quartz-rich sandstone, commonly subarkose or arkose
Fossiliferous Limestone
Bioclastic Limestone (with Brachiopod and Bivalve molds)
Quartz Pebble (with Iron Inclusions)
Silicon Dioxide (SiO2)
Fossilized Shark Tooth
Chondrichthyes tooth
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Fossilized Brachiopod
Brachiopoda (e.g., Atrypa or Rhynchonellida)
Petrified Wood
Silicified wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Red Jasper
Jasper (Silicon Dioxide with Iron inclusions - SiO2)
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Shark Tooth (Otodus obliquus)
Otodus obliquus (Mineralized Apatite / Bio-apatite)
Petrified Wood
Silicified Wood (SiO2)
Granite Cobble
Felsic Intrusive Igneous Rock
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Chert (Yellow or Ochre Jasper variant)
Microcrystalline Quartz (SiO2)
Tumbled dark stone, likely basalt or basaltic pebble
Fine-grained mafic volcanic rock; commonly composed of plagioclase, pyroxene, and minor olivine (basalt)
Red jasper (likely tumbled)
Jasper, microcrystalline quartz/chalcedony (SiO₂), colored mainly by iron oxides
Chert / Flint
Chert (Cryptocrystalline Quartz, SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (specifically Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Chalky/Gray Variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Tumbled brown quartz/chert pebble
Microcrystalline quartz (SiO₂), possibly chert or jasper
Jasper
Silicon Dioxide (SiO2) with impurities
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Polished Unakite (likely)
Unakite: quartz + epidote + pink K-feldspar, commonly with minor chlorite
Chert (often called Flint when dark)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Chert (specifically Black Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Tumbled goldstone-like quartz pebble
Likely iron-stained quartz or jasper; exact identification requires testing
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chert (Jasper/Ironstone variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert
Chert (Microcrystalline Quartz, SiO2)
Chert (and Flint)
Silicon Dioxide (SiO2)
Honey-colored chalcedony (likely carnelian)
Microcrystalline quartz, SiO₂; orange chalcedony colored by iron oxides