Shale
Shale (composition varies: primarily clay minerals and quartz)
Category
Browse organic (non geological) specimens identified by the Rock Identifier community.
Shale
Shale (composition varies: primarily clay minerals and quartz)
Obsidian
Volcanic Glass (SiO2 dominant)
Quartzite
Quartzite (Primary mineral: SiO2)
Grey Quartzite Pebble
Quartzite (primarily SiO2)
Obsidian (Apache Tear)
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
Black Obsidian
Volcanic Glass (felsic)
Rose Quartz
Silicon Dioxide with traces of titanium, iron, or manganese (SiO2)
Quartzite Pebble
Metamorphic Quartzite
Blue Slag Glass
Ferro-silicate glass (Slag)
Obsidian
Volcanic glass (SiO2 - Silicon dioxide predominant composition)
Chert (Field Stone)
Silicon Dioxide (SiO2)
Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2 with iron oxide inclusions
Limestone
Calcium Carbonate (CaCO3)
Chert (Red/Pink variety)
Microcrystalline quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2) with Iron Oxide inclusions
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Jasper/Flint variant)
Microcrystalline Quartz (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert (often called Flint in this variation)
Silicon dioxide (SiO2) - Microcrystalline quartz
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (often called Jasper or Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pyrite in Shaly Matrix
Iron Sulfide (FeS2)
Black Obsidian
Obsidian (Amorphous Silicon Dioxide)
Baltic Amber (Butterscotch variety)
Succinite
Drill Core Sample
Cylindrical Rock Core (Specific mineralogy varies by extraction site)
Quartzite
Metamorphic rock (SiO2)
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Granite
Granite (Felsic Plutonic Rock)
Chert (Brown Variety)
Microcrystalline quartz (SiO2)
Pink Quartzite
Quartzite (SiO2)
Granite / Feldspar gravel
Granite (felsic intrusive igneous rock)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert / Chalcedony (Agatized)
Silicon dioxide (SiO2)
Chert (Limestone-based)
Silicon dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Chert (variant Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)