Banded Chert
Silicon Dioxide (SiO2)
Category
Browse anthropogenic (man made material) specimens identified by the Rock Identifier community.
Banded Chert
Silicon Dioxide (SiO2)
Flint / Chert
Silicon dioxide (SiO2)
Quartzite
Quartzite
Coquina / Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate - CaCO3)
Red Sandstone
Arenite (with Iron Oxide cement)
Coquina
Coquina (Bioclastic Limestone)
Limestone
Calcium Carbonate (CaCO3)
Milky Quartz
Silicon Dioxide (SiO2)
Polished kambaba jasper
Orbicular stromatolitic jasper; microcrystalline quartz (SiO₂) with chlorite/amphibole-rich inclusions
Tiffany Stone
Fluorite-bearing Opalized Breccia
Chert (Flint)
Sedimentary Cryptocrystalline Quartz (SiO2)
Diamond
C
Diamond (or Diamond Simulant like Cubic Zirconia)
Carbon (C) - if Diamond; Zirconium dioxide (ZrO2) - if Cubic Zirconia
Granite (weathered pebble)
Granite (plutonic igneous rock)
Slag Glass
Silicon dioxide with impurities
Chert pebble
Microcrystalline silica (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
Basalt (Vesicular)
Extrusive mafic igneous rock; primarily (Mg, Fe)2SiO4 (Olivine), CaAl2Si2O8 (Plagioclase Feldspar), and Pyroxene
Coquina
Biogenic Limestone (Coquina)
Sandstone Clast
Arenite (primarily SiO2)
River Siltstone / Mudstone Pebble
Siltstone (composed of mixed silicate and carbonate minerals)
Petrified Wood
Silicified Wood (primarily SiO2)
Greenstone, likely serpentine or green jasper
Serpentine-group minerals, chiefly antigorite/lizardite; possibly quartz-rich jasper
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Banded malachite cabochon
Malachite, Cu₂CO₃(OH)₂; the dark bands may be manganese-oxide or other sulfide-rich matrix, and could also indicate a composite or treated specimen
Greenschist
Greenschist (chlorite schist)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
Petrified Wood
Silicified Wood (primarily SiO2)
Conglomerate
Conglomerate Rock
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz with Hematite/Limonite staining
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Scoria
Vesicular Basaltic Glass
Slate
Slate (Foliated metamorphic rock)
Gray Granite
Phaneritic plutonic rock (Granite)
Sandstone
Arenite
Flint
Microcrystalline Quartz (SiO2)
Chert (Arrowhead Fragment)
Cryptocrystalline quartz (SiO2)
Milky quartz with dark host-rock inclusions
Quartz (SiO₂), likely in a granitic or metamorphic matrix
Honey-colored chalcedony (possibly yellow/orange agate or carnelian)
Chalcedony, a microcrystalline variety of quartz; SiO₂. The color may result from iron-oxide inclusions. Exact identification is uncertain from a photograph alone.