Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Category
Not A Geological Specimen
Browse not a geological specimen specimens identified by the Rock Identifier community.
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Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Brachiopod Fossil (Spiriferid)
Phylum Brachiopoda, Order Spiriferida (CaCO3 - Calcium Carbonate)
sedimentary (fossilized organic remains)
Moss Agate Geode Sphere
Silicon Dioxide (SiO2) - Chalcedony with Chlorite or Manganese inclusions
mineral
Amethyst (Raw Cluster)
Silicon Dioxide with iron impurities (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Limonite (Bog Iron)
Limonite (Hydrated iron(III) oxide-hydroxide) - FeO(OH)·nH2O
mineral
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone (Stream-rounded Cobble)
Arenite (composed primarily of SiO2, Silica)
sedimentary
Blue Chalcedony
Silicon Dioxide (SiO2)
mineral
Mixed Mineral Specimens
Mixed Silicates, Oxides, and Phosphates (SiO₂, Ca₅(PO₄)₃(F,Cl,OH), Na₈Al₆Si₆O₂₄Cl₂, etc.)
mineral
Chalcedony (Common Agate pebble)
Silicon Dioxide (SiO2)
mineral
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
mineral
Agate with Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Limonite (Iron Ore)
Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)
Mineral
Pyrite in Matrix (likely Quartz or Schist matrix)
Iron Sulfide (FeS2)
mineral
Schorl (Black Tourmaline) in Quartz and Feldspar
NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Basalt with Epidote (Flowerstone-like texture)
Amygdaloidal Basalt (silicate mineral inclusions)
igneous
Granite
Granite (phaneritic intrusive igneous rock consisting of quartz, feldspar, and mica)
igneous
Chert with Chalcedony/Quartz Vug
Cryptocrystalline Silica (SiO2)
sedimentary
Amethyst and Agate Geode Section
Silicon Dioxide (SiO2) - Crystalline Quartz and Chalcedony
mineral
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Celestite (Celestine) Geode
Strontium Sulfate (SrSO4)
mineral
Quartz (Smoky/Milky variety with matrix)
Silicon Dioxide (SiO2)
mineral
Amber
Fossilized Tree Resin (Generic formula roughly C10H16O)
mineral
Blue Quartz with Graphite/Tourmaline Inclusions
Silicon Dioxide (SiO2) with Carbon (C) or Schorl elements
mineral
Banded Agate
Cryptocrystalline Quartz (SiO2) with iron oxide inclusions
mineral
Carnelian Agate Nodule
Silicon Dioxide (SiO2) - Carnelian Chalcedony
mineral
Quartz / Quartz Geode fragment
Silicon Dioxide (SiO2)
mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Titanium Aura Quartz
Silicon Dioxide (SiO2) coated with Titanium and Niobium
mineral
Fluorite (Rainbow Fluorite)
Calcium Fluoride (CaF2)
Mineral
Sandstone with Liesegang Rings
Arenite with Iron Oxide Liesegang Banding
sedimentary
Schist with Quartz
Mica Schist (contains Muscovite/Biotite and Quartz SiO2)
metamorphic
Obsidian
Volcanic glass
igneous
Black Obsidian
Volcanic Glass (SiO2 + impurities)
igneous
Lapis Lazuli
Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
metamorphic
Opalite
Synthetically produced glass (Silicon Dioxide with metallic inclusions)
Mineraloid (Man-made Glass)
Limestone
Calcium Carbonate (CaCO3)
sedimentary