Milky Quartz (Quartz Vein)
Silicon Dioxide (SiO2)
Category
Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.
Milky Quartz (Quartz Vein)
Silicon Dioxide (SiO2)
Rose Quartz with possible Manganese or Iron inclusions
SiO2 (Silicon Dioxide)
Yellow Quartz (Iron-Stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions
Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
Agate
Banded Chalcedony (SiO2 - Silicon Dioxide)
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Limestone Pebble
Calcium Carbonate (CaCO3)
Granite
Phaneritic Felsic Igneous Rock
Ferruginous Sandstone (Gritstone)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3 and FeO(OH))
Red Chert
Microcrystalline Quartz (SiO2)
Banded Agate
Cryptocrystalline Quartz (SiO2)
Granodiorite (Gneissic texture)
Granodiorite (containing Quartz SiO2, Plagioclase Feldspar, and Biotite)
Cloudy Quartz
Quartz (Silicon Dioxide, SiO2)
Chert (Arrowhead Preform or Flake)
Microcrystalline Quartz (SiO2)
Brecciated Chert
Sedimentary Chert (SiO2) with Calc-Silicate mineralization
Agate
Silicon dioxide (SiO2) - variety of chalcedony
Sandstone
Arenite (SiO2 primarily)
Granite
Granite (Alkali-feldspar granite)
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
Amygdaloidal Basalt
Amygdaloidal Mafic Volcanic Rock
Travertine (Tufa)
Terrestrial Sedimentary Limestone (CaCO3)
Basalt River Pebble
Basalt (Mafic Extrusive Volcanic Rock)
Greenstone (Amygdaloidal Basalt)
Amygdaloidal Basalt (frequently composed of Plagioclase Feldspar, Pyroxene, and Olivine with Chlorite inclusions)
Basalt (tumbled/river-worn)
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Fossilized Wood (with Coal and Limonite)
Petrified Wood (Silicified or Carbonized Flora)
Banded Chert
Silicon Dioxide (SiO2)
Basalt
Mafic volcanic rock, primarily composed of Plagioclase, Pyroxene, and Olivine
Ferruginous Siltstone or Mudstone
Ferruginous Siltstone / Goethitic Sandstone
Greywacke (Briarcliff Schist/Gneiss)
Manhattan Schist / Fordham Gneiss complex
Yellow Quartz (Citrine-colored Quartz)
Silicon Dioxide (SiO2)
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Amethyst
Crystalline Quartz (SiO2 with iron impurities)
Quartz Vein with Iron Staining
Silicon Dioxide (SiO2)
Sandstone (Pebble)
Arenite (primarily SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Milky Quartz (Water-Worn Pebble)
Quartz (Silicon Dioxide, SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt containing Zeolite and Calcite inclusions
Banded Agate (with possible Chalcedony layers)
Silicon dioxide (SiO2)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
Tan Brown Granite
Phaneritic Biotite-Feldspar Granite
Banded Jasper with Hematite or Quartz
Silicon Dioxide (SiO2) with impurities
White Quartz
Silicon Dioxide (SiO2)