Unakite
Unakite (Altered Granite)
metamorphic
Category
Sedimentary Rock (Altered)
Browse sedimentary rock (altered) specimens identified by the Rock Identifier community.
Jasper (specifically Bloodstone or Heliotrope variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary (chemically precipitated)
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)
Banded Agate
Sedimentary Cryptocrystalline Quartz (SiO2)
mineral
Sandstone Concretion
Moqui Marble / Iron-oxide Concretion (SiO2 with Hematite/Goethite)
sedimentary
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
River Pebble Gravel
Hydrothermally modified Clastic Sediment (mainly Quartzite and Chert)
sedimentary
Sandstone (Quartzose Sandstone)
Arenite
sedimentary
Sandstone
Arenite (SiO2 with various cementing agents)
sedimentary
River Pebble (Quartz-rich)
Silicon Dioxide (SiO2) with various inclusions
sedimentary
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Sedimentary Rock
Yellow Jasper
Silicon Dioxide with Iron inclusions (SiO2)
sedimentary
African Turquoise
Teal Jasper (Macro-crystalline Quartz/Sio2 + Inclusions of Copper, Iron, and Manganese)
sedimentary
Chert (Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
River Stone (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) based metamorphosed sandstone
metamorphic or sedimentary
Yellow Chert
Sedimentary cryptocrystalline quartz (SiO2)
sedimentary
Limestone (specifically Dolomitic Limestone)
Calcium Magnesium Carbonate (CaMg(CO3)2)
sedimentary
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
sedimentary
Coral Fossil (Petrified Coral)
Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
sedimentary
Chert (Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Ferruginous Sandstone
Arenite with Iron-oxide cement (composed of Quartz and Limonite/Hematite)
sedimentary
Bauxite
Bauxite (Al2O3·2H2O)
sedimentary
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone (Pebble)
Sandstone (arenite, arkose, wacke depending on composition)
sedimentary
Sedimentary Breccia
Clastic Breccia (CaCO3/SiO2 matrix)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Red Jasper
Silicon dioxide (SiO2) with iron oxide (Fe2O3) inclusions
sedimentary/mineral
Blue Banded Agate (Dyed)
Silicon Dioxide (SiO2) - variety of Chalcedony
mineral
River Chalcedony / Agate
Chalcedony (Silicon Dioxide, SiO2)
mineral
Pyrite on Quartz matrix
Iron Disulfide (FeS2) on Silicon Dioxide (SiO2)
mineral
Amethyst
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
mineral
Agate (Chalcedony)
Cryptocrystalline Silica or Silicon Dioxide (SiO2)
mineral
Biotite Schist
Biotite Schist
Metamorphic
Ocean Jasper
Orbicular Jasper (Silicon Dioxide, SiO2)
sedimentary
Concretion (Sandstone)
Carbonate-cemented Sandstone Concretion
sedimentary
Fossiliferous Shale (with Vertebrate Bones)
Laminated Mudstone containing Fossilized Bone (Apatite)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Jasper (with Agate/Chalcedony inclusions)
Silicon Dioxide (SiO2)
sedimentary
Jasper (Red/Yellow)
Silicon Dioxide (SiO2) with impurities
sedimentary