Chalcedony
Silicon Dioxide (SiO2)
mineral
Category
Mineral (Native Element Alloy)
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Quartz-rich pegmatitic rock, possibly rose quartz with mica
Granitic pegmatite; predominantly quartz (SiO₂), with feldspar and mica
igneous
Biotite-bearing granite
Granite, composed mainly of quartz (SiO₂), potassium feldspar, plagioclase, and biotite mica
igneous
Polished black obsidian pyramid/block
Obsidian — natural volcanic glass, chiefly rhyolitic silica (approximately 70–75% SiO₂)
igneous
Banded Gneiss
Banded Gneiss (High-grade Metamorphic Rock)
metamorphic
Bauxite (Iron-stained Chert / Ironstone Aggregate)
Hydrous aluminum oxide mixture (mainly Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Goethite α-Fe3+O(OH))
sedimentary
Limonite Concretion
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)wnH2O)
sedimentary
Bauxite
Bauxite (Al2O3·2H2O)
sedimentary
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral
Limonite Geode (Ironstone Concretion)
Goethite/Limonite FeO(OH)·nH2O
sedimentary
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Bauxite (Pisolitic Bauxite)
Bauxite (mixture of Hydrous Aluminum Oxides)
sedimentary
Greenstone (Epidote/Chlorite Rich Rock)
Metabasalt (often contains Epidote Ca2Al2(Fe3+;Al)(SiO4)(Si2O7)O(OH))
metamorphic
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz River Pebble with Algae
Silicon Dioxide (SiO2) with organic biofilm
metamorphic or igneous
Quartz (Pink/Orange Variety)
Silicon Dioxide (SiO2)
mineral
Lapis Lazuli
Lapis Lazuli (Mineral composition: Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2, Calcite, and Pyrite)
metamorphic
Rough Quartz (Alluvial Pebbles)
Silicon Dioxide (SiO2)
mineral
Greenstone with Epidote or Quartz veins
Metabasalt (Greenstone facies)
metamorphic
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Chert (specifically Green Chert/Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
mineral
Quartz (Gravel fragment)
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Tumbled pale green calcite
Calcite (CaCO₃)
mineral
Rough Green Tourmaline (Verdelite)
Elbaite (Complex Silicate) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
mineral
Yellow Quartz (or Citrine Quartz)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Banded Agate (specifically Carnelian Agate)
Silicon Dioxide (SiO2) - Chalcedony variety
mineral
Garden Quartz (Lodolite / Inclusion Quartz)
Quartz with inclusions (SiO2 with various mineral inclusions)
gemstone
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Azurite and Malachite
Cu3(CO3)2(OH)2 (Azurite) / Cu2CO3(OH)2 (Malachite)
mineral
Zircon
Zircon (ZrSiO4)
Mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Muscovite Mica in Quartz Matrix
Muscovite (KAl2(AlSi3O10)(OH)2) in Quartz (SiO2)
mineral
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary