Amethyst Geode
Quartz (SiO₂) with iron impurities
Mineral/Igneous (secondary formation)
Category
Anthropogenic (Man Made Material Processed By Nature)
Browse anthropogenic (man made material processed by nature) specimens identified by the Rock Identifier community.
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Granite
Granite (Felsic Plutonic Rock)
Igneous
Sandstone
Arenite (primarily SiO2)
sedimentary
Banded Gneiss
Gneiss (typically quartz, feldspar, mica, amphibole composition)
metamorphic
Sandstone (Ferruginous)
Arenite (Fe2O3 rich)
sedimentary
Granite
Granite (Felsic Plutonic Rock)
igneous
Quartzite
Quartzite (primarily SiO2)
metamorphic
Blue Agate (Dyed Chalcedony)
Silicon Dioxide (SiO2)
mineral
Emerald
Beryl (Be3Al2(SiO3)6) with trace Chromium/Vanadium
mineral
Green Aventurine
Aventurine (a variety of Quartz, SiO2)
Mineral
Aragonite (Star Cluster or Twinned variety)
Aragonite (Calcium Carbonate, CaCO3)
mineral
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Amygdaloidal Basalt
Amygdaloidal Basalt (with secondary mineral infilling)
igneous
Yellow Quartz (Citrine or Yellow Jasper)
Silicon Dioxide (SiO2)
mineral
Smoky Quartz Geode Cluster
Silicon Dioxide (SiO2)
mineral
Peacock Ore (Chalcopyrite)
Chalcopyrite (CuFeS2)
mineral
Red Sandstone
Arenite (with Iron Oxide)
sedimentary
Granite (Light-colored quartz/feldspar variety)
Granite (composed primarily of Quartz SiO2 and Feldspar KAlSi3O8)
igneous
Granite
Felsic Intrusive Igneous Rock
igneous
Brown Sandstone
Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)
sedimentary
Granite
Phaneritic Plutonic Igneous Rock (composed of Quartz, Feldspar, and Mica)
igneous
Granite
Granite (phaneritic felsic intrusive rock)
igneous
Granite
Granite (Phaneritic Quartz-Feldspar Rock)
igneous
Limestone
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Peridot (likely, given the color and bead form)
Olivine, variety Peridot (Mg,Fe)2SiO4
Mineral
Pink Granite (Water-worn Cobble)
Phaneritic Felsic Intrusive Igneous Rock
igneous
Granite
Phaneritic Igneous Rock (Granitic)
igneous
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
Igneous
Granite
Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)
igneous
Granite
Granite (composed of Quartz, Feldspar, and Mica/Amphibole)
igneous
Emerald
Beryl (Be3Al2Si6O18) with trace amounts of Chromium and/or Vanadium
mineral
Seraphinite
Clinochlore (a variety of the chlorite group)
mineral
Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)
Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.
Metamorphic, Mineral (within a rock type)
Orange Quartz (Citrine Quartz)
Silicon Dioxide (SiO2)
mineral
Blue Agate (Dyed)
Silicon Dioxide (SiO2) - Variety of Chalcedony
mineral
Yellow Quartz (Chalcedony/Citrine Pebble)
Silicon Dioxide (SiO2)
mineral
Granite
Phaneritic Plutonic Felsic Rock
igneous
Dyed Agate
Silicon Dioxide (SiO2) - Variety Agate / Chalcedony
mineral
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Granite
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8), and Mica)
igneous
Granite
Phaneritic intrusive igneous rock (consisting mainly of Quartz, Alkali Feldspar, and Plagioclase)
igneous