Quartz pebble
Silicon Dioxide (SiO2)
mineral
Category
Sedimentary Or Igneous (Secondary Formation)
Browse sedimentary or igneous (secondary formation) specimens identified by the Rock Identifier community.
Learn about Sedimentary Or Igneous (Secondary Formation) in the encyclopedia
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Green Apophyllite and Stilbite on Quartz Cluster
Apophyllite-(K) (KCa4(Si8O20)(F,OH)·8H2O), Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O), Quartz (SiO2)
Mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix
igneous
Granite
Intrusive Igneous Rock
igneous
Quartz in Matrix
Silicon Dioxide (SiO2) in host rock matrix
mineral
Banded River Cobble with Mafic Dike
Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion
igneous and sedimentary
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
mineral
Jasper with Purple Fluorite or Chalcedony
Silicon Dioxide (SiO2) with mineral inclusions
sedimentary
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
mineral
Druzy Quartz (on Geode Fragment)
Silicon Dioxide (SiO2)
mineral
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Greenstone Pebble
Metabasalt / Greenschist
metamorphic
Puddingstone (Gowganda)
Gowganda Formation Conglomerate
sedimentary
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Magnetite
Magnetite (Fe3O4)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Pyrite (on Quartz matrix)
Iron Disulfide (FeS2)
mineral
Yellow Chalcedony (Agate/Jasper mix)
Silicon Dioxide (SiO2)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Granite
Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)
Igneous
Banded Agate (specifically Lake Superior Agate type)
Silicon Dioxide (SiO2) - variety Chalcedony
mineral
Sardonyx or Carnelian Agate
Silicon Dioxide (SiO2) with iron impurities
mineral
Magnetite
Magnetite (Fe3O4)
mineral
Gneiss
Gneiss
metamorphic
Quartz (likely a weathered/tumbled piece)
Quartz (SiO₂)
Mineral
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Igneous
Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Quartz (likely tumbled or naturally water-worn)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Prehnite
Calcium aluminum silicate hydroxide, Ca2Al(AlSi3O10)(OH)2
mineral
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
mineral
Purple Lepidolite with Quartz
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Granite
Granite
igneous
Sandstone (Limonitic/Iron-stained)
Sandstone (containing Quartz, SiO2, and Limonite, FeO(OH)·nH2O)
sedimentary
Gneiss
Granitic Gneiss
metamorphic
Amygdaloidal Basalt
Extrusive mafic igneous rock with amygdules
igneous
Turquoise and Hematite
Turquoise: CuAl6(PO4)4(OH)8·4H2O; Hematite: Fe2O3
mineral
Quartz
Quartz (SiO2)
Mineral