Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Category
Browse organic (non geological) specimens identified by the Rock Identifier community.
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Banded Chert with Quartz Veining
Microcrystalline Quartz (SiO2)
Slag
Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)
Quartzite
Quartzite (composed primarily of SiO2)
Shale or Siltstone
Sedimentary Rock (Siliciclastic)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Chert (White Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (often colloquially referred to as Flint)
Chert (Cryptocrystalline Quartz, SiO2)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Chert (Green variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (Microcrystalline Quartz), SiO2
Chert (vuggy variety)
Microcrystalline silica (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (specifically Yellow Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (Primary mineral: Silicon Dioxide, SiO₂)
Mahogany Obsidian
Obsidian (SiO2 + Fe2O3)
Limonite (Yellow Ochre)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
Chert / Flint
Chert (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Gastropod Steinkern (Fossil Snail Internal Mold)
Class Gastropoda (Internal Mold)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Unable to identify - Image contains non-geological items
Quartzite
Quartzite (primarily SiO2)
Coquina Limestone (Fossiliferous Limestone)
Calcareous bioclastic sedimentary rock (CaCO3)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Brown Variety)
Silicon dioxide (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (and its variety Flint)
Silicon Dioxide (SiO2) - Microcrystalline or cryptocrystalline Quartz
Coquina / Fossiliferous Limestone
Coquina (composed primarily of Calcium Carbonate / CaCO3)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Tektite (Indochinite)
Tektite (Lechatelierite-rich silica glass)
Black Obsidian
Volcanic Glass (predominantly SiO2)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Chert (specifically Flint Arrowhead)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Obsidian
Obsidian (volcanic glass; primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)