Banded Agate (Mutton-fat or Pork-stone variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Sedimentary / Mineral
Category
Mineralological Specimen
Browse mineralological specimen specimens identified by the Rock Identifier community.
Greywacke (River Slikkenstone)
Greywacke (Impure Sandstone)
sedimentary
Yellow Quartz Pebble (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
mineral
Basalt River Pebble
Aphanitic Mafic Basalt
igneous
Chert Breccia (Yellow Jasper)
Silicon Dioxide (SiO2) - Brecciated Chert
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Corundum (Ruby Variety)
Corundum (Al2O3)
mineral
Dyed Blue Agate (Slab)
Agate (Variety of Chalcedony/Microcrystalline Quartz), SiO2
mineral
Quartzite River Cobble
Quartzite (SiO2)
metamorphic
Jasper with Hematite inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
sedimentary
Jasper or Agate-bearing Chert
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
sedimentary
River Quartzite Siltstone
Quartz-rich Meta-siltstone (SiO2 dominated)
metamorphic
Chert / Quartz Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Vesicular Basalt or Scoria
Basalt (extrusive volcanic rock)
igneous
Yellow Agate
Chalcedony (cryptocrystalline Quartz), SiO2
mineral
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)
mineral
Iron Slag
Iron smelting byproduct (Glassy/vesicular silicate)
anthropogenic / industrial byproduct
Septarian Nodule (Dragon Stone)
Septarian concretion (Complex of Calcite, Aragonite, and Limestone/Clay)
sedimentary
Vesicular Basalt with Oxidation
Scoriaceous Olivine Basalt (Mafic volcanic rock)
igneous
Milky Quartz with Iron Inclusions
Quartz (Silicon Dioxide, SiO2)
mineral
Iron Meteorite (likely Chondrite or Iron-Nickel fragment)
Siderite (Iron Meteorite), primarily Fe-Ni (Iron-Nickel) alloy
igneous
Travertine
Terrestrial Sedimentary Limestone (CaCO3)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2)
sedimentary
Felsic Igneous Rock (likely Rhyolite or weathered Granite)
Felsic Volcanic/Plutonic Rock
igneous
Quartzite with Sandstone/Iron staining
Metamorphic Quartzite (SiO2)
metamorphic
Fuchsite in Quartz (Aventurine Quartz)
K(Al,Cr)2(AlSi3O10)(OH)2 (Fuchsite) + SiO2 (Quartz)
metamorphic
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
metamorphic
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
sedimentary
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Granite
Phaneritic plutonic rock (approx. 20-60% quartz, 35-90% feldspar)
igneous
Calcite
Calcium Carbonate (CaCO3)
mineral
Sandstone Pebble with Iron Staining
Clastic Sedimentary Rock (primarily Quartz with Fe2O3 oxides)
sedimentary
Chrysoberyl (Cyclic Twin)
Beryllium Aluminum Oxide (BeAl2O4)
mineral
Blue Chalcedony Geode (with Quartz Druzy)
Silicon Dioxide (SiO2) - Microcrystalline variety of Quartz
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartzite
Silicon Dioxide (SiO2)
metamorphic
Cavansite
Cavansite (Ca(VO)Si4O10·4H2O)
mineral
Gneiss (specifically a weathered or stream-worn specimen)
Gneiss (Foliated Metamorphic Rock)
metamorphic
Yellow Quartzite (River Cobble)
Quartzite (mainly SiO2)
metamorphic
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
igneous
Basalt Pebble
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Epidote
Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)
mineral