Quartz (White or Milky Quartz Pebble)
Quartz (Silicon Dioxide, SiO2)
Category
Browse man made object (coin) specimens identified by the Rock Identifier community.
Quartz (White or Milky Quartz Pebble)
Quartz (Silicon Dioxide, SiO2)
Pink Feldspar (Orthoclase)
Orthoclase Feldspar (KAlSi3O8)
Pink Orthoclase Feldspar with Dendrites
Orthoclase (KAlSi3O8) with Manganese Oxide dendrites
Scoria
Vesicular Basaltic Glass (comprised primarily of volcanic glass/silica with plagioclase, pyroxene, and olivine crystals)
Red Jasper (Banded Jasper)
Jasper (Silicon Dioxide, SiO2)
Scoria (Basaltic Lava Rock)
Vesicular Basalt
Fluorite
Calcium Fluoride (CaF2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper variation)
Silicon dioxide (SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Ocean Jasper
Orbicular Jasper (Silicon Dioxide, SiO2)
Quartz (Crystal Point/Fragment)
Silicon Dioxide (SiO2)
Rough Quartz (likely Milky or Smoky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Slate
Slate (Regional metamorphic rock composed primarily of quartz, illite, and chlorite)
Jasper (Iron-rich)
Silicon Dioxide (SiO2) with Hematite (Fe2O3) impurities
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Basalt
Mafic Igneous Rock
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Chert (Nodular Chert)
Microcrystalline Silica (SiO2)
Basalt River Stone
Basalt
Granite (specifically Rapakivi Granite)
Phaneritic Felsic Igneous Rock (Granite)
Limestone
Calcium Carbonate (CaCO3)
Conglomerate
Conglomerate (clastic sedimentary rock)
Pumice
Pumice (a highly vesicular volcanic glass)
Banded Black Onyx (Chalcedony)
Silicon Dioxide (SiO₂)
Chert (Nodular Chert)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide inclusions
Corundum (Sapphire in Host Rock)
Corundum (Aluminum Oxide, Al2O3)
Clear Quartz
Crystalline Silicon Dioxide (SiO2)
Sandstone
Arenite
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Sandstone, Quartzite, and River Pebbles
Silicon Dioxide (SiO2) based Sedimentary/Metamorphic structures
Milky Quartz (Tumbled Pebble)
Silicon Dioxide (SiO2)
Greenstone
Greenschist (composed of actinolite, chlorite, and epidote)
Gastropod Fossil (Internal Mold)
Phylum Mollusca, Class Gastropoda (Steinkern)
Gastropod Steinkern (Fossilized Snail Cast)
Phylum Mollusca, Class Gastropoda (Commonly CaCO3 or SiO2 after replacement)
Jade (likely Jadeite or Nephrite)
Jadeite (NaAlSi2O6) or Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)
Quartzite Pebble
Quartzite (primarily SiO2)