Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Category
Mineral, Sediment
Browse mineral, sediment specimens identified by the Rock Identifier community.
Concretion
Various mineral compositions, typically carbonate or iron oxide cemented sediment
Sedimentary
Chert (Banded)
Microcrystalline Quartz (SiO2)
sedimentary
Banded Chert (River Siltstone)
Microcrystalline Quartz (SiO2)
sedimentary
Greywacke
Lithic Sandstone (Greywacke - (SiO2+Al2O3+Fe2O3))
sedimentary
Gastropod Steinkern (Fossil Snail Internal Mold)
Class Gastropoda (Internal Mold)
sedimentary
Red Jasper
Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3)
Mineral (variety of Chalcedony/Quartz)
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Specular Hematite with Quartz
Ferric oxide (Fe2O3) and Silicon dioxide (SiO2)
Mineral
Quartz (River Pebble)
Silicon Dioxide (SiO2)
mineral
Gold Flake / Placer Gold
Native Gold (Au)
mineral
Gemstone Sand (Mineral Assortment)
Mixed Mineral Concentrates (Commonly including Quartz SiO2, Garnet X3Y2(SiO4)3, and Tourmaline (Na,Ca)(Li,Mg,Al)3(Al,Fe,Mn)6(BO3)3(Si6O18)(OH,F)4)
mineral
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
metamorphic
Graywacke (River Cobble)
Graywacke (Lithic Sandstone)
sedimentary
Greywacke
Greywacke sandstone
sedimentary
Gastropod Internal Mold (Steinkern)
Class Gastropoda fossil mold (Phylum Mollusca)
sedimentary
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
mineral
Biotite (Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Kambaba Jasper (Crocodile Jasper)
Rhyolite containing Fossilized Cyanobacteria (Stromatolite)
sedimentary
Shale
Fissile mudrock (composed of clay-sized particles and detrital grains)
sedimentary
Crushed Stone / Greywacke
Greywacke (Indurated Sandstone)
sedimentary
Jasper (Red/Brown)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Bumblebee Jasper
Calcite-bearing Volcanic Tuff containing Sulfur and Arsenic (Orpiment/Realgar)
sedimentary
Devil's Toenail
Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)
sedimentary
Fossilized Brachiopod
Phylum Brachiopoda (replaced by Calcite/CaCO3)
sedimentary
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)
sedimentary
Fossilized Shark Tooth in Matrix
Otodus sp. (likely Otodus obliquus)
sedimentary
Amber
Succinite (fossilized resin, C10H16O)
mineral
Fossil Shark Tooth (Otodus obliquus)
Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))
sedimentary (fossiliferous)
Septarian Nodule (or Mudstone with Septarian Cracking)
Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Claystone)
sedimentary
Red Jasper
Jasper (Silicate Mineral - SiO2)
sedimentary
Shungite
Shungite (carbon-rich Precambrian rock)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Mica in Quartz Host
Muscovite (KAl2(AlSi3O10)(OH)2) in Quartz (SiO2)
igneous
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Mineral/Fossil (Sedimentary context)
Graywacke (Sandstone)
Graywacke Sandstone
sedimentary
Favosites Fossil (Honeycomb Coral)
Favosites sp. (Extinct genus of tabulate coral)
sedimentary
River Stone (Basalt or Siltstone with banding)
Polished Basaltic or Siliciclastic River Cobble
igneous or sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxides (Goethite)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron hydroxides (Goethite)
sedimentary
Fossil Sand Dollar (Echinoidea)
Phylum Echinodermata, Class Echinoidea (likely Dendraster or Scutella)
sedimentary