Quartz Pebble
Silicon Dioxide (SiO2)
Category
Browse mineral_rock specimens identified by the Rock Identifier community.
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz River Pebble with Algae
Silicon Dioxide (SiO2) with organic biofilm
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
Lapis Lazuli
Na8[Al6Si6O24]S2 (Lazurite component), a rock composed primarily of Lazurite, Calcite, and Pyrite
Rhodochrosite
Rhodochrosite (MnCO3)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Greenstone
Metabasalt / Greenstone
Quartz (Quartzite)
Silicon Dioxide (SiO2)
Granite
Felsic intrusive igneous rock
Granite
Felsic intrusive igneous rock
Limonite / Ironstone Nodule
Hydrated Iron Oxide (FeO(OH)·nH2O)
Gneiss (Banded Gneiss)
Gneiss
Limonite / Ironstone
FeO(OH)·nH2O
Magnetite (Lodestone variant potential)
Magnetite (Fe3O4)
Limonite (Iron Ore)
Limonite (mixed iron hydroxides, primarily FeO(OH)·nH2O)
Sardonyx Agate Sphere
Cryptocrystalline Quartz (SiO2) with iron oxide inclusions
Turquoise
Turquoise (Hydrated phosphate of copper and aluminium) CuAl6(PO4)4(OH)8·4H2O
Fossilized Shark Tooth (Megalodon or Carcharocles species fragment)
Otodus megalodon / Carcharocles spp. (Apatite / Calcium Phosphate)
Bauxite
Aluminium ore (Hydrated aluminium oxides AlOx(OH)3-2x)
Milky Quartz Pebble with Matrix
Quartz (SiO2)
Polished Mexican “Crazy Lace” agate tower
Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide inclusions
Milky Quartz
Silicon Dioxide (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Sandstone (with banding)
Arenite (primarily SiO2)
Sandstone with Iron Oxide (Limonite/Hematite)
Ferruginous Sandstone (SiO2 with FeO(OH)·nH2O)
Quartz Vein in Host Rock (Gneiss/Schist)
Silicon Dioxide (SiO2) within a metamorphic matrix
Fluorite
Calcium Fluoride (CaF2)
Quartz with Feldspar
Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)
Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Bauxite
Hydrated aluminum oxides (mixture of gibbsite, boehmite, and diaspore)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Milky quartz (rough quartz fragment)
Quartz, silicon dioxide (SiO₂)
Obsidian
Volcanic glass (SiO2-rich extrusive igneous rock)
Limonite / Brown Iron Ore
Hydrous Iron Oxide (FeO(OH)·nH2O)
Gneiss
Gneiss
Green Fluorite
Calcium Fluoride (CaF2)
White Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Greenstone
Protolith of basalt, diabase, or gabbro; often contains minerals like chlorite, actinolite, and epidote
Quartz (Iron-Stained or Milky)
Silicon Dioxide (SiO2)
Limonite Concretion
Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O
Quartz (Grain/Pebble)
Silicon Dioxide (SiO2)