Amethyst
Quartz (Silicon Dioxide with Iron impurities), SiO2
Category
Browse mineralological specimen specimens identified by the Rock Identifier community.
Amethyst
Quartz (Silicon Dioxide with Iron impurities), SiO2
Amazonite
KAlSi3O8 (Potassium aluminum silicate - blue-green variety of Microcline)
Thunderegg
Agate-filled Rhyolitic Nodule (SiO2)
Amethyst Geode
Silicon dioxide (SiO2) with iron impurities
Red Jasper
Silicon Dioxide (SiO2) - variety Jasper
Amazonite
Potassium Aluminum Silicate (KAlSi3O8)
Olivine in Basalt
Peridotite / Forsterite ((Mg,Fe)2SiO4)
Quartz Crystal Fragment
Silicon Dioxide (SiO2)
Moonstone (specifically Rainbow Moonstone / White Labradorite)
White Labradorite (Feldspar Group: (Na,Ca)(Al,Si)4O8)
Amethyst
Silicon Dioxide (SiO2) with trace Iron (Fe3+)
Agate
Silicon Dioxide (SiO2)
Snowflake Obsidian
Volcanic glass containing Spherulites (SiO2)
Quartz (Milky and Smoky variety)
Silicon Dioxide (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Chert / Chalcedony (likely carnelian or flint variety)
Silicon Dioxide (SiO2)
Clear/White Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Pyrite in Quartz (Drill Core)
Silicon Dioxide (SiO2) with Iron Sulfide (FeS2) inclusions
Quartz with Inclusions
Silicon Dioxide (SiO2) with various mineral inclusions
Quartz (Citrine or Smoky variant)
Silicon Dioxide (SiO2)
Pyrite in Matrix (Quartz/Schist)
Iron Sulfide (FeS2)
Limonite (often after Hematite or Goethite)
Limonite (FeO(OH)·nH2O)
Ocean Jasper
Spherulitic Chalcedony (SiO2)
Quartzite Pebble
Recrystallized Quartz (SiO2)
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Agate Geode
Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety
Quartz Vein in Metamorphic Rock
Silicon Dioxide (SiO2) within Metasedimentary host
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Calcite
Calcium Carbonate (CaCO3)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Porphyritic Andesite
Andesite (porphyritic variety)
Jasper in Quartz (River Cobble)
Silicon Dioxide (SiO2) with Ferric Iron inclusions
Jasper (Cream/Yellow variety)
Silicon Dioxide (SiO2) with impurities
Ferruginous Quartz
Quartz (Silicon Dioxide) - SiO2 with Iron Oxide inclusions
Smoky Quartz with Calcite/Quartz Veining
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz with Mica inclusions (Pegmatite)
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
Titanium Quartz (Rough)
Titanium-included Silicon Dioxide (SiO2 + Ti)
Milky Quartz with Inclusions
Silicon Dioxide (SiO2)
Citrine (Heat-treated Amethyst)
Silicon Dioxide (SiO2) with iron impurities
Copper-bearing Quartz (likely Malachite on Quartz matrix)
Cu2CO3(OH)2 (Malachite) on SiO2 (Quartz)
Iron-stained Quartzite
Metamorphic Quartz (SiO2) with limonite/hematite staining