Hag Stone
Perforated sedimentary rock (typically flint, chert, or limestone)
sedimentary
Category
Mineral (Processed Alloy)
Browse mineral (processed alloy) specimens identified by the Rock Identifier community.
Sandstone (Greywacke)
Arenite / Wacke (SiO2 + varied clasts)
sedimentary
Serpentinite
Serpentinite (composed primarily of mineral group (Mg,Fe,Ni,Al)3Si2O5(OH)4)
metamorphic
Porphyritic Igneous Pebble / Porphyry
Porphyritic Igneous Rock
igneous
Dalmatian Stone (often called Dalmatian Jasper)
Peralkaline Quartz-Feldspar Rock with Arfvedsonite (formerly believed to be Jasper)
igneous
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcedony replacement)
Mineral / Fossil
Greenstone / Serpentinite
Serpentinite (composed largely of Serpentine group minerals, Mg3Si2O5(OH)4)
metamorphic
River Cobble (Quartzite-rich Sandstone)
Clastic Sedimentary Rock (Litharenite/Quartzite transition)
sedimentary
River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)
Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)
Sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite and Quartz inclusions
sedimentary
Feldspathic Granite (likely Syenite or Granite Pegmatite)
Phaneritic Acidic Igneous Rock (KAlSi3O8 dominant with SiO2)
igneous
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)
sedimentary
Granite (Granitic Pegmatite/Porphyry)
Felsic intrusive igneous rock (Quartz, Feldspar, Mica composition)
igneous
Black Onyx
Silicon Dioxide (SiO2)
mineral
Pink Dyed Agate (Banded Chalcedony)
Silicon dioxide (SiO2) - variety Chalcedony
mineral
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Mineraloid / Industrial Byproduct
Bauxite
Bauxite (mixture of Gibbiste Al(OH)3, Boehmite ̳-AlO(OH), and Diaspore ́-AlO(OH))
sedimentary
Pyrite-bearing Schist
Pyritic Quartz-Mica Schist with FeS2 inclusion
metamorphic
Granite (Pink/Potassium-rich)
Pink Granite (contains K-Feldspar, Quartz, and Plagioclase)
igneous
Sand Tiger Shark Tooth
Carcharias taurus
fossil
Hawk's Eye (Blue Tiger's Eye)
Quartz (fibrous crocidolite variety)
Mineral
Granite
Intrusive Felsic Igneous Rock
igneous
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
sedimentary
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
sedimentary
Chert
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide
mineral
Dyed Agate Geode
Silicon Dioxide (SiO2) with artificial pigment
mineral
Slag (Industrial By-product)
Anthropogenic Vitreous Silica/Iron Silicate
mineral
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
mineral
River Cobble (likely Basalt or Rhyolite)
Extrusive Igneous Rock (Mafic or Intermediate)
igneous
Petrified Wood
Silicified wood (primarily SiO2)
fossil
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily SiO2)
sedimentary
Serpentine
Serpentinite (a rock composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite; general formula (Mg, Fe)3Si2O5(OH)4)
metamorphic
Agate
Agate (Silicon Dioxide, SiO2)
mineral
Granite
Granite (a plutonic igneous rock composed primarily of quartz and feldspar)
Igneous Rock
Red Jasper
Red Jasper (SiO2 with Fe2O3 impurities)
sedimentary