Petrified Wood
Silicified Wood (SiO2)
metamorphic
Category
Organic (Often Found By Beachcombers)
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Chert (Banded Variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (specifically River Stone / Jasper variety)
Microcrystalline Quartz (SiO2)
sedimentary
Shale (possibly)
Shale (fine-grained clastic sedimentary rock)
sedimentary
Brachiopod Fossil (Spiriferid)
Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)
sedimentary (fossilized organic remain)
Note: Item is not a geological specimen
Homo sapiens (Dermal Appendage: Pilus)
Organic / Biological
Petrified Wood
Silicified wood (SiO2 - Silicon Dioxide)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Petrified Wood
Silicified wood (Quartz, SiO2)
metamorphic
Carnelian (Orange Chalcedony)
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)
metamorphic
Chert (Jasper/Flint variety)
Microcrystalline silicon dioxide (SiO2)
sedimentary
Chert (with Liesegang Banding)
Microcrystalline quartz (SiO2)
sedimentary
Pearl (nacre)
Calcium Carbonate (mostly CaCO3 as Aragonite) and Conchiolin
Organic Mineraloid
Limonite
Hydrous Iron Oxide (often Goethite FeO(OH), Lepidocrocite γ-FeO(OH), and other amorphous iron oxyhydroxides)
Mineral
Amber
Succinite (Formula: C10H16O)
Organic Mineraloid
Stichtite (often found in Serpentinite)
Stichtite Mg6Cr2CO3(OH)16·4H2O
Mineral
Amber (Burmite)
Fossilized tree resin (Succinite variant)
Organic mineraloid
Red Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert (Quartz Variety)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Amber (Butterscotch/Egg Yolk Variety)
Succinite (Approx. C10H16O)
Organic Gemstone
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Pearl (Imitation or Cultured)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
Mineraloid (Organic)
Pearl (in a decorative hair comb setting)
Calcium carbonate (CaCO3) primarily as Aragonite, bonded with Conchiolin
Organic Mineraloid
Amber
Succinite (C10H16O)
Organic Mineraloid
Amber
Succinite (formula varies, primarily C10H16O)
Mineraloid (Organic)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Selenite
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
mineral
Popcorn
Zea mays everta (P. Wilson) (Botanical name for the corn variety)
Organic/Biogenic
Quartzite
Quartzite (primarily SiO2)
metamorphic
Septarian Nodule (Septarian Dragon Stone)
Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)
sedimentary
Argetine Blue Agate (Chalcendony variant)
Silicon Dioxide (SiO₂)
mineral
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Chert (Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
mineral
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lithium-bearing Phyllosilicate)
mineral
Slag
Ferrous Slag (Siliceous industrial waste)
Anthropogenic (Man-made industrial byproduct)
Iron Slag
Anthropogenic Vitreous Ferrous Silicate
industrial byproduct (anthropogenic)