Basalt with Secondary Mineral Inclusions
Amygdaloidal Basalt (Mafic volcanic rock, primarily Augite and Plagioclase)
igneous
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Iron-stained Quartz
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3/FeO(OH))
mineral
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Jasper with Quartz Vein
Silicon Dioxide (SiO2) with impurities
sedimentary
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2)
mineral
Yellow Quartz (Citrine or Yellow Jasper)
Silicon Dioxide (SiO2)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)
Chert (microcrystalline quartz)
Metamorphic Rock
Pumice
Vesicular Rhyolite or Dacite
igneous
Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
igneous
Pumice or Scoria
Vesicular volcanic rock
Igneous
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Shale or Slate with Quartz Veins
Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins
Metamorphic, likely Sedimentary with Quartz veins
Granite
Phaneritic Plutonic Felsic Rock (K-Feldspar + Quartz + Plagioclase)
igneous
Vesicular Basalt
Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 (Pyroxene) and (Ca,Na)Al(Al,Si)Si2O8 (Plagioclase Feldspar)
igneous
Gold Ore in Quartz/Schist
Auriferous Quartz and Sulfide-bearing Schist
Metamorphic/Igneous (Hydrothermal)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Sandstone (Banded Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with iron oxide impurities)
sedimentary
Basalt with Iron Oxidation
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Andesite
Andesite (Intermediate Extrusive Igneous Rock)
igneous
Pink Granite with Quartz Vein
Phaneritic Plutonic Felsic Rock (K-feldspar + Quartz + Plagioclase + Mica)
igneous
Clear Quartz Point
Silicon Dioxide (SiO2)
mineral
Dalmatian Stone
Peralkaline rhyolite with arfvedsonite (formerly incorrectly called Dalmatian Jasper)
igneous
River Pebble (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) mixture with varied clastic minerals
sedimentary/metamorphic
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Granite Cobble
Granite (Phaneritic Igneous Rock)
igneous
Sandstone (Quartzose)
Arenite (SiO2 principal)
sedimentary
Chert (Chalk-associated Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Field Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Rock Salt (Halite)
Halite (Sodium Chloride, NaCl)
mineral
Milky Quartz (Water-worn Pebble)
Quartz (Silicon Dioxide, SiO2)
mineral
Sandstone (Ferruginous/Banded)
Clastic Terrigenous Sandstone (SiO2 with Fe2O3 cement)
sedimentary
Iron Slag
Ferrous Slag (complex silicate and oxide byproduct)
industrial byproduct (anthropogenic)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Conglomerate (Asphaltic/Anthropogenic)
Clastic sedimentary rock / Bituminous mixture
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Basalt with Plagioclase Phenocrysts (Porphyritic Basalt)
Porphyritic Basalt (primarily SiO2, Al2O3, FeO, MgO, CaO)
igneous
Concretion (Sandstone)
Sandstone Concretion
sedimentary
Granite
Granite (compositional mixture of Quartz, Feldspar, and Mica)
igneous