Petrified Wood
Silicified wood (SiO2)
sedimentary
Category
Organic (Anthropogenic)
Browse organic (anthropogenic) specimens identified by the Rock Identifier community.
Learn about Organic (Anthropogenic) in the encyclopedia
View all →
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
fossil
Green Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
metamorphic
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Black Marble with Quartz Veining
Metamorphosed Limestone (Recrystallized CaCO3)
metamorphic
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
sedimentary
Amber (Copal)
Organic gemstone, fossilized tree resin (often immature amber or copal)
Mineral
Hardpan Nodule / Ferruginous Sandstone
Ferruginous Sandstone (Fe-cemented sediment)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Amber (Black)
Amber (succinite, retinite, etc., specifically, heavily included/dark varieties)
Mineraloid
Septarian Pebble
Septarian nodule / Concretion
sedimentary
Polished petrified wood
Silicified wood, primarily microcrystalline quartz (SiO₂) replacing organic tissue
fossil
Amber
(C10H16O)n – an amorphous organic substance, primarily composed of polymerized isoprenoids.
Mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Petrified Wood
Silicified wood (Quartz / Chalcedonized wood, SiO2)
sedimentary
Anthracite Coal
Anthracite (Metamorphic/High-grade Sedimentary Coal)
sedimentary
Graphite
Graphite (Carbon, C)
Mineral
Pink Opal / Peruvian Opal
Hydrated amorphous silicon dioxide (SiO2·nH2O)
Mineral
Petrified Wood
Silicified wood (primarily quartz, SiO2)
fossil
Fossilized Gastropod (Snail)
Class Gastropoda (internal mold or 'steinkern')
sedimentary
Pet Rock (Man-made Quartzite or Granite Cobble)
Silicon dioxide (SiO2) mixture; commonly composed of Quartz, Feldspar, and Mica
igneous or metamorphic (base stone); anthropogenic (decoration)
Terracotta (Man-made ceramic brick fragment)
Baked clay / High-iron ceramic (Silicate-based ceramic)
Anthropogenic material (Man-made sedimentary mimic)
Amber
Amber (Fossilized Tree Resin)
Mineral
Petrified Wood
Silicified wood (primarily SiO2)
sedimentary
Chert (Arrowhead or Projectile Point)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Septarian Nodule (Septarian Dragon Stone)
Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)
sedimentary
Shungite
Carbonaceous rock (primarily amorphous carbon)
Mineraloid
Concrete with Aggregate
Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)
anthropogenic (human-made) sedimentary-like material
Slag Glass
Amorphous Silica / Glass Slag
industrial byproduct (anthropogenic rock-like material)
Sea Glass (Teal/Turquoise)
Amorphous Silica (SiO2) with trace metal oxides
Anthropogenic (Man-made material processed by nature)
Sea Glass (Turquoise/Aqua)
Amorphous Silica (SiO2) with transition metal dopants
Anthropogenic (Man-made material processed by nature)
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Red Jasper (beads)
SiO₂ (Silicon Dioxide)
Mineral, variety of chalcedony (microcrystalline quartz)
Chert / Flint
Chert (varieties include Flint)
Sedimentary
Shale
Shale
sedimentary
Fossilized wood fragment
Petrified wood; commonly silicified fossil wood (SiO₂ replacing organic tissue)
fossil
Petrified Wood
Silicified wood (Quartz / Chalcedony replacement)
fossil
Chert / Flint
Chert (varietal name for microcrystalline quartz). Chemical formula: SiO₂
Mineral
Pyrite
Pyrite (FeS2)
Mineral