Pyrite
Iron Disulfide (FeS2)
Category
Browse mixed: igneous and sedimentary specimens identified by the Rock Identifier community.
Pyrite
Iron Disulfide (FeS2)
Yellow Quartz (Citrine Quartz or Yellow Chalcedony)
Silicon Dioxide (SiO2)
Carnelian
Carnelian (Microcrystalline Quartz, SiO2)
Gneiss
Metamorphic rock of high-grade regional metamorphism
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Gneiss
Gneiss (High-grade metamorphic rock)
Quartz River Pebbles
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Greenstone / Greenschist
Greenschist facies metamorphic rock
Tiger's Eye (Oeil de Tigre)
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
Milky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Citrine Quartz
Citrine (Silicon Dioxide, SiO2)
Citrine (Heat-treated Amethyst)
Silicon Dioxide (SiO2) with iron impurities
Quartz with Iron Staining
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
Moonstone (specifically White Moonstone/Adularia)
Potassium aluminum silicate ((K,Na)AlSi3O8)
Smoky Quartz
Silicon Dioxide (SiO2)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8) with Albite
Citrine
Silicon Dioxide (SiO2)
Hypersthene
Hypersthene (formula: (Mg,Fe)SiO3)
Magnetite
Iron(II,III) oxide (Fe3O4)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz (Yellow/Citrine variety)
Crystalline Silicon Dioxide (SiO2)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Muscovite Mica
Muscovite / KAl2(AlSi3O10)(OH)2
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Quartz Crystal (specifically Rock Crystal)
Silicon Dioxide (SiO2)
Unakite
Unakite Epidosite (Granite with epidote and orthoclase)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Chert on Volcanic Host Rock
Sedimentary Chert (SiO2) within Basalt or Andesite
Quartz Pebble
Crystalline Silica (SiO2)
Granitic Sand
Detrital sediment (predominantly Quartz, Feldspar, and Mica)
Sandstone (Ferruginous)
Sandstone (primarily SiO2 with Iron Oxide cement)
Sandstone
Arenite (primarily Quartz, SiO2)
Botryoidal Quartz
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed of SiO2, CaCO3, or iron oxides)
Sandstone
Arenite (SiO2 based)
Banded Chert / Jasper
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2)
Chert / Chalcedony (Agatized)
Silicon dioxide (SiO2)
Sandstone
Arenite (SiO2 principal)