Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Category
Browse organic (non rock) specimens identified by the Rock Identifier community.
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Tektite (Indochinite)
Tektite (Amorphous silica glass, SiO2 with impurities)
Conglomerate (Red Sandstone variety)
Clastic Sedimentary Rock (Conglomeratic Sandstone)
Red Quartzite River Stone
Metamorphic Rock (composed mainly of Quartz, SiO2)
Emerald in Matrix
Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities
Anthracite Coal
Anthracite (Carbon-based sedimentary-derived metamorphic rock)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (SiO2)
Chert (Flint)
Chert (Cryptocrystalline Silicon Dioxide, SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Quartzite Pebble
Quartzite (mostly SiO2)
Dark metamorphic rock, likely biotite schist or gneiss
Quartz–feldspar–biotite metamorphic rock; exact identification requires a fresh surface and testing
Shungite
Fullerene-bearing carbonaceous rock
Ironstone Concretion (Boxwork)
Siderite-Limonite Concretion (FeO(OH)·nH2O)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Quartzite
Quartzite (primarily SiO2)
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Limestone / Dolomite
Calcium Carbonate (CaCO3) / Calcium Magnesium Carbonate (CaMg(CO3)2)
Polished ocean jasper or orbicular chalcedony
Microcrystalline quartz (SiO₂), likely chalcedony with feldspar or other mineral inclusions
Limestone Concretion (Botryoidal/Calcareous Nodules)
Calcium Carbonate Concretion (CaCO3)
Chert (River Stone)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Quartzite with Iron Oxide Vein
Metamorphic Quartzite (SiO2 with Hematite/Limonite impurities)
Jasper
Silicon dioxide (SiO2)
Chert Pebble
Chert (Microcrystalline Quartz, SiO2)
Chert (Holey Stone)
Microcrystalline Quartz (SiO2)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Shungite
Shungite (carbon-rich Precambrian rock)
Banded Chert
Silicon Dioxide (SiO2)
Quartz with Mica Schist Matrix
Quartz (SiO2) in Mica Schist Matrix
Chert (Field Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon dioxide (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Tektite (specifically Indochinite)
Tektite (Natural silica glass)
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Silicon dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)