Rock Identifier

Category

Organic (Non Geological)

Browse organic (non geological) specimens identified by the Rock Identifier community.

Quartz-rich metamorphic pebble (Milky quartz with possible feldspar and mica; likely quartzite or quartz-veined metamorphic rock) — metamorphic

Quartz-rich metamorphic pebble

Milky quartz with possible feldspar and mica; likely quartzite or quartz-veined metamorphic rock

Petrified Wood (Silicified Wood (primarily SiO2)) — fossil

Petrified Wood

Silicified Wood (primarily SiO2)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 + impurities)

Obsidian (Volcanic glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic glass (SiO2 + impurities)

Quartzite (Quartzite (chiefly SiO2)) — metamorphic

Quartzite

Quartzite (chiefly SiO2)

Obsidian (Amorphous volcanic glass (70-75% SiO2)) — igneous

Obsidian

Amorphous volcanic glass (70-75% SiO2)

Obsidian Arrowhead (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian Arrowhead

Volcanic Glass (predominantly SiO2)

Obsidian (Volcanic Glass (Amorphous SiO2-rich glass)) — Igneous

Obsidian

Volcanic Glass (Amorphous SiO2-rich glass)

Black Obsidian (Obsidian (Volcanic Glass)) — igneous

Black Obsidian

Obsidian (Volcanic Glass)

Fossil tooth (Mineralized vertebrate tooth; exact animal and species cannot be determined from the image) — fossil

Fossil tooth

Mineralized vertebrate tooth; exact animal and species cannot be determined from the image

Banded Chert (River Pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Obsidian (Volcanic Glass (70-75% SiO2)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2)

Black Obsidian (Obsidian (Volcanic Glass, ~70% SiO2)) — igneous

Black Obsidian

Obsidian (Volcanic Glass, ~70% SiO2)

Obsidian (Volcanic Glass) — igneous

Obsidian

Volcanic Glass

Weathered agate or chalcedony nodule (Microcrystalline quartz (SiO₂), likely agate/chalcedony with iron-oxide staining) — mineral

Weathered agate or chalcedony nodule

Microcrystalline quartz (SiO₂), likely agate/chalcedony with iron-oxide staining

Fossilized Shell Fragment (Invertebrate fossil (phylum Mollusca)) — fossil

Fossilized Shell Fragment

Invertebrate fossil (phylum Mollusca)

Rounded river pebble, likely basalt or andesite (Fine-grained mafic to intermediate volcanic rock; exact identification requires testing) — igneous

Rounded river pebble, likely basalt or andesite

Fine-grained mafic to intermediate volcanic rock; exact identification requires testing

Snowflake Obsidian (Spherulitic Volcanic Glass (primarily SiO2)) — igneous

Snowflake Obsidian

Spherulitic Volcanic Glass (primarily SiO2)

Black Tourmaline (Schorl) (Sodium Iron Aluminum Borosilicate (NaFe2+3Al6(BO3)3Si6O18(OH)4)) — mineral

Black Tourmaline (Schorl)

Sodium Iron Aluminum Borosilicate (NaFe2+3Al6(BO3)3Si6O18(OH)4)

Green Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Green Chert

Microcrystalline Quartz (SiO2)

Black tourmaline (likely schorl) (Schorl, NaFe3Al6(BO3)3Si6O18(OH)4) — mineral

Black tourmaline (likely schorl)

Schorl, NaFe3Al6(BO3)3Si6O18(OH)4

Green cabochon gemstone pendant (Indeterminate; likely dyed green turquoise, chrysoprase, or opaque beryl set with blue/clear accent stones) — gemstone

Green cabochon gemstone pendant

Indeterminate; likely dyed green turquoise, chrysoprase, or opaque beryl set with blue/clear accent stones

Blue Slag Glass (Man-made Silicon Dioxide (Amorphous)) — Anthropogenic (Man-made)

Blue Slag Glass

Man-made Silicon Dioxide (Amorphous)

Anthropogenic (Man-made)

Obsidian (Volcanic Glass (70% or more SiO2)) — igneous

Obsidian

Volcanic Glass (70% or more SiO2)

Anthracite Coal (Anthracite) — metamorphic

Anthracite Coal

Anthracite

Pink coral and green-stone jewelry (Likely pink coral (calcium carbonate, CaCO₃) set with an unidentified green stone; the image is too indistinct to identify the green material reliably.) — gemstone

Pink coral and green-stone jewelry

Likely pink coral (calcium carbonate, CaCO₃) set with an unidentified green stone; the image is too indistinct to identify the green material reliably.

Limestone with Chert Nodule (Carbonate rock (CaCO3) with Microcrystalline Silicon Dioxide (SiO2) inclusion) — sedimentary

Limestone with Chert Nodule

Carbonate rock (CaCO3) with Microcrystalline Silicon Dioxide (SiO2) inclusion

Petrified Wood (Silicified Wood (primarily SiO2)) — fossil

Petrified Wood

Silicified Wood (primarily SiO2)

Banded Sandstone (Liesegang Rings) (Sedimentary sandstone with Iron oxide precipitates) — sedimentary

Banded Sandstone (Liesegang Rings)

Sedimentary sandstone with Iron oxide precipitates

Petrified wood (Silicified fossil wood; commonly quartz (SiO₂) replacing wood tissue) — fossil

Petrified wood

Silicified fossil wood; commonly quartz (SiO₂) replacing wood tissue

Chert (Concretion or Nodular Variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Concretion or Nodular Variety)

Microcrystalline Quartz (SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Polished Black Obsidian (Volcanic Glass (70-75% SiO2)) — igneous

Polished Black Obsidian

Volcanic Glass (70-75% SiO2)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Graphitic schist (probable) (Graphite-bearing mica schist; chiefly quartz, mica, and graphite) — metamorphic

Graphitic schist (probable)

Graphite-bearing mica schist; chiefly quartz, mica, and graphite

Polished quartz-rich pebble, possibly jasper or quartzite (Quartzite or chalcedony-bearing jasper; predominantly SiO₂) — metamorphic

Polished quartz-rich pebble, possibly jasper or quartzite

Quartzite or chalcedony-bearing jasper; predominantly SiO₂

Opalite (Opalescent Glass (SiO2 + coloring agents)) — Mineral (Synthetic/Man-made)

Opalite

Opalescent Glass (SiO2 + coloring agents)

Mineral (Synthetic/Man-made)

River Siltstone / Mudstone Pebble (Siltstone (composed of mixed silicate and carbonate minerals)) — sedimentary

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Rounded sandstone cobble (Clastic sandstone, likely quartz-rich (quartz arenite or arkose)) — sedimentary

Rounded sandstone cobble

Clastic sandstone, likely quartz-rich (quartz arenite or arkose)

Snowflake Obsidian (Spherulitic Obsidian (Amorphous volcanic glass with Phenocrysts of Cristobalite)) — igneous

Snowflake Obsidian

Spherulitic Obsidian (Amorphous volcanic glass with Phenocrysts of Cristobalite)

Petrified Wood (Silicified wood (primarily Silicon Dioxide, SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)