Amethyst (Quartz)
Silicon Dioxide (SiO2)
mineral
Category
Mineral (Tectosilicate)
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
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Biotite on Matrix
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Limonite pseudomorph after Pyrite
Goethite/Limonite FeO(OH)·nH2O
mineral
Geode (Unopened)
SiO2 (Quartz-filled Sedimentary Nodule)
sedimentary
Emerald in Matrix
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Opal
Hydrated silica (SiO2 "NH2O)
mineraloid
Rutilated Quartz
Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions
mineral
Alexandrite in Matrix
Chrysoberyl (BeAl2O4 with Chromium impurities)
mineral
Banded Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Amethyst (Ametrine or Bicolor Quartz variant)
Silicon Dioxide (SiO2) with iron impurities
mineral
Citrine Quartz Crystal Cluster
Silicon Dioxide (SiO2) with iron impurities
mineral
Amethyst in Matrix
Silicon Dioxide with Iron Impurities (SiO2)
mineral
Moqui Marble (Ironstone Concretion)
Iron Oxide Concretion (Fe2O3)
sedimentary
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with Iron Oxide)
metamorphic
Amethyst
Amethyst (Silicon Dioxide - SiO2)
mineral
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
mineral
Quartz Geode
Crystalline Silicon Dioxide (SiO2)
mineral
Sulfide Ore (likely Galena and Sphalerite in Quartz)
Lead-Zinc Ore (PbS and ZnS)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Menilite Opal (Goddess Stone)
Menilite Opalescent Silex (Amorphous Hydrated Silica)
sedimentary
Geode (Unbroken)
Silicon Dioxide (SiO2) usually as Microcrystalline Quartz or Chalcedony
sedimentary
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
mineral
Fuchsite Schist
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2) in Schist
metamorphic
Blue Lace Agate
Silicon Dioxide (SiO2)
mineral
Rose Quartz
Rose Quartz (SiO2 with trace titanium, iron, or manganese)
mineral
Pink Orthoclase Feldspar with Dendrites
Orthoclase (KAlSi3O8) with Manganese Oxide dendrites
mineral
Tektite (Indochinite)
Tektite (impactite), primarily high-silica glass (SiO2)
igneous
Amethyst Quartz
Amethyst (SiO2 with Iron impurities)
mineral
Sunstone
Andesine-Labradorite Feldspar ((Ca,Na)(Al,Si)4O8)
mineral
Malachite
Malachite (Cu2CO3(OH)2)
mineral
Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities
mineral
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
mineral
Emerald (Beryl)
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
mineral
Chalcedony (specifically Agate or Carnelian variety)
Cryptocrystalline Silica (SiO2)
mineral
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
mineral
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
mineral
Epidote (likely Unakite component or Epidosite)
Epidote (Ca2(Al2Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Rose Quartz
Silicon Dioxide (SiO2) with trace rutile/dumortierite
mineral
Celestine (or Celestite) on Matrix
Celestine (SrSO4)
mineral
Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Moonstone (Orthoclase Feldspar)
(K,Na)AlSi3O8
mineral
Fulgurite
Fulgurite (Lechatelierite-rich variety)
metamorphic