Granite
Granite (a plutonic rock)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Granite
Granite (a plutonic rock)
Fossilized Shark Tooth
Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)
Chert (specifically Jasper or Flint variant)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Smooth River Pebble)
Silicon Dioxide (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Green Sandstone
Glauconitic Sandstone
Chert (variant Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Basalt
Extrusive Igneous Rock
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Pink Granite
Phaneritic Plutonic Igneous Rock (high K-feldspar)
Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
Granite
Felsic intrusive igneous rock
Quartz Geode
Silicon Dioxide (SiO2)
Tumbled chert or flint pebble
Microcrystalline quartz (SiO₂), likely chert; exact variety uncertain from the image
Petrified Wood
Silicified Wood (SiO2)
Chert (Polished River Pebble)
Chert (SiO2)
Quartzite River Stone
Quartzite (SiO2)
Serpentine (Serpentinite)
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Grey Limestone Pebble
Limestone (Calcium Carbonate - CaCO3)
Slate with Quartz Vein
Foliated Metamorphic Rock (Mainly Quartz, Muscovite, Chlorite)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (Black Flint)
Silicon Dioxide (SiO2)
Pearl
Calcium Carbonate (CaCO3) in the form of orthorhombic Aragonite and Conchiolin
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Basalt
Vesicular Basalt
Sandstone
Sedimentary rock composed mainly of sand-sized minerals or rock grains
Sandstone
Arenite (SiO2 based)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
Fossil Coral
Rugosa or Tabulata coral fossil
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Agatized Chert)
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Common Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (often called Flint when dark)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)