Coarse-grained Granite
Phaneritic Granite (contains Quartz, Feldspar, and Mica)
Category
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Coarse-grained Granite
Phaneritic Granite (contains Quartz, Feldspar, and Mica)
Granite
Granite (a plutonic igneous rock)
Quartzite
Quartzite (primarily SiO2)
Black Tourmaline (Schorl)
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
Granite
Phaneritic Felsic Intrusive Igneous Rock
Basalt with Quartz Veins
Vesicular or aphanitic Basalt with SiO2 (Quartz) intrusions
Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Basalt (Polished River Stone)
Basalt (Extrusive Mafic Volcanic Rock)
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene minerals)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Gneiss
Gneiss
Chert (and/or Siltstone River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Flint nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Serpentine
Serpentinite (rock) containing serpentine minerals (e.g., Antigorite, Lizardite, Chrysotile)
Basalt
Extrusive Mafic Igneous Rock (composed primarily of plagioclase feldspar and pyroxene)
Orange Quartzite (Tumbled)
Quartzite (SiO2)
Jasper and Chert Conglomerate
Ferruginous Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Cryptocrystalline Quartz (SiO2)
Serpentine
Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4
Basalt
Basalt (Igneous Volcanic Rock)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Basalt
Basalt (composition of Plagioclase feldspar and Pyroxene)
Basalt
Basalt
Howlite
Howlite (Ca2B5SiO9(OH)5)
Pumice
Pumicite (Amorphous glass with varying chemical composition, often rhyolitic)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, Mg3Si2O5(OH)4)
Quartz
Silicon Dioxide (SiO2)
Basalt with Mineral Vein (Cobble)
Basalt (with likely Quartz/Calcite vein)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Milky Quartz
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)
Conglomerate
Conglomerate (clastic sedimentary rock)
Jasper (Banded Jasper)
Silicon Dioxide (SiO2) with impurities
Druzy Quartz on Chalcedony Matrix
Silicon Dioxide (SiO2)
Basalt with Desert Varnish
Mafic Volcanic Rock (Fe/Mg rich Silicate)
Basalt
Basalt (High-iron/magnesium silicate rock)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Goethite
Goethite (α-FeO(OH))
Vesicular Rhyolite
Extrusive igneous rock (high-silica rhyolite)
Fossilized Coral
Scleractinian Anthozoa (Fossilized Calcium Carbonate, CaCO3)