Scoria (Lava Rock)
Scoria (Mafic Volcanic Rock)
igneous
Category
Mineral Within Sedimentary Rock
Browse mineral within sedimentary rock specimens identified by the Rock Identifier community.
Chert (Flint variety)
Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2
sedimentary
Pink Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Sandstone with Bedding Planes
Arenite (Sedimentary rock composed primarily of sand-sized minerals)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Chert
Microcrystalline silica (SiO2)
sedimentary
Amethyst
Quartz (Silicon Dioxide) - SiO2
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Chert (Limestone-based)
Silicon Dioxide (SiO2) within Carbonate host
sedimentary
Conglomerate
Conglomerate (Rock composed predominantly of rounded clasts > 2mm)
sedimentary
Eclogite
Eclogite (comprising Omphacite and Garnet)
metamorphic
Jasper with Quartz Vein
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Asphalt (Road Aggregate)
Asphalt concrete / Bituminous mixture
anthropogenic sedimentary (technolith)
Red Sandstone
Clastic Terrigenous Sedimentary Rock (primarily SiO2 with Fe2O3 coating)
sedimentary
Rutilated Quartz (likely Citrine or Smoky Quartz with Rutile inclusions)
SiO2 with TiO2 inclusions (Quartz with Rutile)
Mineral
Fossilized Coral (Petoskey-like or Favosites)
Anthozoa (Fossilized Coral)
sedimentary
Fossil Shell in Sedimentary Matrix
Bivalvia (fossil) in Calcium Carbonate Matrix
sedimentary
Chert (often called Flint when dark)
Sedimentary cryptocrystalline quartz (SiO2)
sedimentary
Chert (Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Fossil Shark Tooth (embedded in matrix)
Lamniformes (likely Cretalamna or Squalicorax) within phosphatic/calcareous matrix
sedimentary
Chert (Jasper)
Microcrystalline Quartz (SiO2) with iron oxide impurities
sedimentary
Chert (Field Stone/Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Brachiopod Fossil in Shale
Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)
sedimentary
Crinoid Fossil in Limestone
Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)
sedimentary
Mica Schist with Iron Staining
Mica Schist
metamorphic
Druzy Quartz Geode (likely Smokey Quartz variety)
Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.
Mineral structure/Rock
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Quartz Druze (on Matrix)
Silicon Dioxide (SiO2)
mineral
Chert (Golden/Yellow Variety)
Microcrystalline Silica (SiO2)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Granite
Granite (a felsic intrusive igneous rock)
igneous
Rock Crystal Quartz
Quartz (SiO₂)
Mineral
Coquina
Bioclastic Limestone
sedimentary
Banded Gneiss
Gneiss (pronounced 'nice')
metamorphic
Belemnoit Fossil (Sea Squid Fossil)
Belemnitida (Order within Cephalopoda)
sedimentary
Conglomerate
Conglomerate (clastic sedimentary rock type)
sedimentary
Coquina / Fossiliferous Limestone
Calcareous bioclastic sedimentary rock (CaCO3)
sedimentary