Granitic Pegmatite
Coarse-grained Igneous Rock (Granitic composition: KAlSi3O8, SiO2)
Category
Browse man made alloy (metallic) specimens identified by the Rock Identifier community.
Granitic Pegmatite
Coarse-grained Igneous Rock (Granitic composition: KAlSi3O8, SiO2)
Rose Quartz
Silicon Dioxide (SiO2)
Yellow Jade
Jadeite or Nephrite (NaAlSi2O6 or Ca2(Mg,Fe)5Si8O22(OH)2)
Chert (specifically Flint or Common Chert)
Chert (Cryptocrystalline Silica, SiO2)
Jasper (specifically Yellow Jasper and Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 principal)
Chert (Nodular)
Cryptocrystalline Quartz (SiO2)
Zoisite with Ruby (Anyolite)
Anyolite (Ca2Al3(SiO4)3(OH) + (Hb, Al, Cr)2O3)
Bauxite
Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)
Pumice
Pumice (a highly vesicular extrusive igneous rock, primarily amorphous silica)
Greywacke
Dirty Sandstone (Lithic wacke)
Granite
Granite (Mainly Quartz SiO2, K-Feldspar KAlSi3O8, and Plagioclase)
Limestone
Calcium Carbonate (CaCO3)
Calcite
Calcite (CaCO3)
Milky Quartz
Silicon Dioxide (SiO2)
Coquina
Biogenic Limestone (Coquina)
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
Kidney Stone
Calcium Oxalate (CaC2O4), Uric Acid, or Struvite
Red Mudstone (Siltstone)
Lutite (primarily Quartz and Clay minerals with Hematite)
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Chert / Flint
Silicon Dioxide (SiO2)
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Obsidian (Apache Tear)
Amorphous Volcanic Glass (SiO2 + impurities)
Calcite
Calcium Carbonate (CaCO3)
Quartzite (Iron-stained)
Quartzite (SiO2 with iron oxides)
Smoky Quartz (Faceted Beads)
Silicon Dioxide (SiO2)
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Granite
Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Granite
Granite
Shale
Fissile mudstone (Shale)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
Feldspar-rich Pegmatite
Granitic Pegmatite (principally KAlSi3O8)
Quartz Mica Schist
Mica-Quartz Schist (Chemical: SiO2 + KAl2(AlSi3O10)(OH)2)
Green Quartzite
Quartzite (SiO2)
Quartz River Cobble
Silicon Dioxide (SiO2)
Septarian Nodule (Thunder Egg)
Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)
Jasper
Silicon dioxide (SiO2) with impurities
Granite
Phaneritic Felsic Igneous Rock
Chert (Iron-Stained)
Microcrystalline Quartz (SiO2)