Milky Quartz
Silicon Dioxide (SiO2)
Category
Browse mineral like byproduct (often mistaken for igneous rock or meteorite) specimens identified by the Rock Identifier community.
Milky Quartz
Silicon Dioxide (SiO2)
Granite
Granite (a common rock type, not a single mineral species)
Pink Granite
Phaneritic Felsic Igneous Rock (composed primarily of K-Feldspar, Quartz, and Mica)
Basalt
Mafic volcanic rock, primarily composed of Plagioclase, Pyroxene, and Olivine
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Orbicular Rhyolite (Rainforest Jasper)
Rhyolite containing Spherulites (SiO2 with impurities)
Red Sandstone
Arenite (primarily SiO2 with hematite/iron oxide coating)
Moonstone
Orthoclase Feldspar (KAlSi3O8)
Basalt with Quartz Veins
Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Quartz Pebble (with Mica or Iron staining)
Silicon Dioxide (SiO2)
Quartz Pebble (Sea Glass-like texture)
Silicon Dioxide (SiO2)
Basalt with Calcite Veins
Basalt (Mafic Volcanic Rock)
Ferruginous Quartz
Quartz (Silicon Dioxide) - SiO2 with Iron Oxide inclusions
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Mexican Crazy Lace Agate
Silicon Dioxide (SiO2) with iron and aluminum inclusions
Pyrite (Iron Pyrite)
Iron Sulfide (FeS2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Soapstone / Steatite
Steatite (primarily Talc, Mg3Si4O10(OH)2)
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
Chalcedony Nodule (Commonly known as Agate or Chert)
Microcrystalline Quartz (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Granite
Granite (Phaneritic Quartz-Feldspar intrusive rock)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Amazonite
Microcline (variety Amazonite), K(AlSi3O8)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Carnelian Agate Nodule
Silicon Dioxide (SiO2) - Carnelian Chalcedony
Diorite (Salt and Pepper Rock)
Diorite
Gneiss
Foliated Metamorphic Rock (Gneiss)
Hag Stone
Porous sedimentary rock (typically Flint, Chert, or Sandstone) with naturally occurring holes
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Schist
Mica Schist (primarily Muscovite [KAl2(AlSi3O10)(OH)2] or Biotite)
Basalt with Amygdules
Amygdaloidal Basalt
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Greenschist / Greenstone
Greenschist facies metabasite
Quartz with Mica/Chlorite inclusions
Silicon Dioxide (SiO2) with phyllosilicate inclusions
Limonite (Iron Ore/Sandstone mixture)
Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix
Greenstone / Greenstone Pebble
Greenschist (metamorphosed basalt or gabbro)
Sandstone Beach Pebble
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide coating)