Sandstone (Quartz Arenite)
Sandstone (Chemical formula: primarily SiO2)
sedimentary
Category
Not A Natural Rock (Man Made Composite)
Browse not a natural rock (man made composite) specimens identified by the Rock Identifier community.
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
White Precious Opal
Hydrated Silica (SiO2·nH2O)
mineral
Chert (specifically Yellow or River Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Black Onyx
Cryptocrystalline Quartz (SiO2)
mineral
River Chalcedony / Agate
Chalcedony (Silicon Dioxide, SiO2)
mineral
Serpentinite (Serpentine Rock)
Serpentinite is a rock composed of one or more serpentine group minerals, chiefly antigorite, chrysotile, and lizardite, with the general formula (Mg,Fe)3Si2O5(OH)4. Often includes other minerals like magnetite, talc, and chromite.
Metamorphic Rock
Jasper
Jasper (Silica/Quartz) - SiO2
mineral
Red Jasper
Jasper (a variety of Chalcedony, SiO₂ with iron oxide inclusions)
Mineral
Sandstone (likely Quartzose Sandstone with mineral staining)
Arenite (composed mainly of SiO2)
sedimentary
Granite (tumbled pebble)
Granite (Plutonic Igneous Rock)
Igneous Rock
Sandstone (likely with Quartz Veining)
Arenite (primarily SiO2)
sedimentary
Red Scoria (Lava Rock)
Scoria (Vesicular Basalt/Andesite)
igneous
Bauxite
Bauxite (Al(OH)3, AlO(OH))
sedimentary
Chiastolite (Andalusite)
Al2SiO5
metamorphic
Gold in Quartz Matrix
Native Gold (Au) with Quartz (SiO2) and Slate/Shale
mineral
Sandstone (Pebble)
Arenite (primarily SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Red Jasper
Red Jasper (variety of Chalcedony, SiO₂)
Mineral
Gold Nugget
Native Gold (Au)
mineral
Quartz (possibly milky quartz)
Quartz (Silica; SiO₂)
Mineral
Red Jasper (Banded Jasper)
Jasper (Silicon Dioxide, SiO2)
sedimentary
Granite
Granite (Felsic Plutonic Rock)
igneous
Amber (Simulated/Faturan Style)
Resin mix (Likely Phenolic/Celluloid if synthetic, Succinite if natural)
Organic Gemstone (not a mineral)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Basalt
Extrusive mafic igneous rock
igneous
Greenstone
Greenschist (composed of actinolite, chlorite, and epidote)
metamorphic
Quartz (Crystal Point/Fragment)
Silicon Dioxide (SiO2)
mineral
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and clay inclusions
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Fluorite (specifically Rainbow Fluorite or Purple Fluorite)
Calcium Fluoride (CaF2)
mineral
Quartz Vein in Host Rock (Gabbro or Basalt)
Silicon Dioxide (SiO2) with Mafic Silicates
metamorphic/igneous
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (Greywacke/Siltstone variant)
Clastic Sedimentary Rock (composed primarily of Quartz SiO2 and Feldspar)
sedimentary
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
sedimentary
Banded Agate (likely Carnelian Agate or Sardonyx)
Agate is a common name for a microcrystalline variety of Quartz (SiO₂), specifically a form of Chalcedony.
Sedimentary Rock (technically a variety of Chalcedony)
Chert (Nodular Chert)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Diorite (Spotted or Dalmatian Stone pattern)
Diorite
igneous
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
mineral
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
mineral