Petrified Wood
Silicified Wood (SiO2)
metamorphic
Category
Organic (Zoogenic)
Browse organic (zoogenic) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
sedimentary
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Septarian Nodule
Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Banded Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Jasper (likely Brown or Brecciated)
Jasper (Silicon Dioxide, SiO2)
sedimentary
Banded Chert
Cryptocrystalline Quartz (SiO2)
sedimentary
Red Jasper
Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
sedimentary
Petrified Wood (Silicified Wood)
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
mineral
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
mineral
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
metamorphic
Chert (specifically Jasper or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Gastropod Fossil (Internal Mold)
Phylum Mollusca, Class Gastropoda (Steinkern)
sedimentary
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
mineral (silicate-replaced organic material)
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (Iron-stained River Cobble)
Microcrystalline Quartz (SiO2)
sedimentary
Graphite
Graphite (C)
mineral
Bituminous Coal
Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)
sedimentary
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)
metamorphic
Fossilized Wood (Petrified Wood)
Silicified Wood (primarily quartz/chalcedony replacing organic matter)
Sedimentary (with some aspects of mineral replacement)
Travertine (Tufa)
Calcium Carbonate (CaCO3)
sedimentary
Chert (Grey-Green Var.)
Silicon Dioxide (SiO2)
sedimentary
Wood Beads (Palmwood/Ebony)
Various species for wood, but often refers to woods like Palmwood (e.g., Borassus flabellifer) or Ebony (Diospyros spp.) for their distinctive grain and hardness.
Organic Gem Material (Botanical)
Pink Opal
Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions
Mineraloid
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)
metamorphic
Septarian Nodule (Dragon Stone)
Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)
sedimentary
Chert (specifically a stream-worn Chert Nodule)
Sedimentary Cryptocrystalline Quartz (SiO2)
sedimentary
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Man-made Object/Uncertain Mineral
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
metamorphic
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
sedimentary
Black Marble with Quartz Veining
Metamorphosed Limestone (Recrystallized CaCO3)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
sedimentary