Sandstone (Quartzose Sandstone)
Arenite
Category
Browse sedimentary (secondary classification for a weathered mineral specimen) specimens identified by the Rock Identifier community.
Sandstone (Quartzose Sandstone)
Arenite
Corundum (Ruby/Sapphire crystal)
Al2O3 (Aluminum Oxide)
Amygdaloidal Rhyolite
Amygdaloidal Rhyolite (Felsic volcanic rock)
Chert / Chalcedony (likely carnelian or flint variety)
Silicon Dioxide (SiO2)
Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Yellow Quartz (Iron-Stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions
Amethyst Geode
Silicon Dioxide (SiO2) with trace Iron (Fe3+) impurities
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Jasper with Hematite Inclusions
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)
Chert (specifically Flint)
Cryptocrystalline Quartz (SiO2)
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Milky Quartz with inclusions
Quartz (Silicon Dioxide, SiO2)
Iron-Stained Quartz (Riverside Cobble)
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
Gneiss (specifically Pink Gneiss)
Gneiss (high-grade regional metamorphic rock)
Quartz / Quartzite
Quartz (Silicon Dioxide, SiO2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix
Yellow Quartzite (or Quartz River Pebble)
Silicon Dioxide (SiO2)
Basalt
Mafic volcanic rock, primarily composed of Plagioclase, Pyroxene, and Olivine
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Chert (Quartz)
Microcrystalline Silica (SiO2)
Jasper in Quartz (River Cobble)
Silicon Dioxide (SiO2) with Ferric Iron inclusions
Yellow Chalcedony (Carnelian/Yellow Agate)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Turquoise (likely stabilized or Howlite/Magnesite imitation)
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Diorite (Salt and Pepper Rock)
Phaneritic Plutonic Diorite; chemical composition roughly 52-63% silica (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Purple Chalcedony (likely dyed Agate)
Silicon Dioxide (SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Rhodochrosite
Manganese Carbonate (MnCO3)
Blue Sapphire
Corundum (Al2O3)
Red Jasper
Silicon dioxide (SiO2) with iron oxide inclusions
Chert (Chalky variety)
Microcrystalline Quartz (SiO2)
Calcite
Calcium Carbonate (CaCO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Gold Nugget
Native Gold (Au)
Agate
Silicon Dioxide (SiO2)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Oolitic Limestone
Oolite (Sedimentary rock composed of CaCO3)