Quartz Crystal
Silicon Dioxide (SiO2)
mineral
Category
Not A Geological Specimen
Browse not a geological specimen specimens identified by the Rock Identifier community.
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Flagstone (likely sandstone or slate)
Flagstone is a paving form, not a single rock species; likely thin-bedded sandstone, with possible slate pieces
sedimentary
Dark gray rock fragment (unidentified)
Undetermined; the image does not show enough detail for reliable identification
igneous
Tumbled Clear Quartz
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Host Rock
Silicon dioxide (SiO2) veining in silicate matrix
sedimentary
Fossiliferous Chert (with Fossil Shells)
Silicon Dioxide (SiO2) with biogenic inclusions
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz Crystal
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Basalt with Quartz Veining
Basalt (SiO2-rich veins)
igneous
Man-made Polished Porcelain Tile (Artificial Geologic Lookalike)
Fused Silicate Ceramic with Alumina (Synthetic Kaolinite derivative)
Synthetic (Ceramic)
Tumbled Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Small pale rock fragment
Indeterminate; possibly quartz, calcite, or a weathered feldspar-rich fragment
mineral
Gossan (with Limonite and Hematite)
Gossanous iron-oxide rock (Fe2O3 · nH2O)
sedimentary
Quartz with Chlorite or Epidote inclusions
Silicon Dioxide (SiO2) with inclusions
mineral
Weathered greenish-gray rock fragment
Unidentified fine-grained mafic rock, possibly basalt or greenstone
igneous
Gowganda Tillite (Puddingstone)
Gowganda Formation Conglomerate
sedimentary
Road-surface aggregate (crushed stone)
Unidentifiable mixed lithic aggregate; likely basaltic/andesitic fragments with feldspar, quartz, and weathered rock
igneous
Mineral Specimen Collection (Galena, Quartz, Calcite, Hematite, etc.)
Mixed Mineral Assemblage (PbS, SiO2, CaCO3, Fe2O3, ZnS, etc.)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Fossilized Bivalve
Phylum Mollusca
fossil
Quartz Mineral
Silicon Dioxide (SiO2)
mineral
Concretion, likely ironstone or carbonate-rich
Mineral-cemented sedimentary concretion; exact composition cannot be determined visually
sedimentary
Chert (within Limestone matrix)
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Porphyritic volcanic rock, possibly porphyritic andesite
Likely andesite porphyry; exact identification requires close examination
igneous
Quartz
Silicon Dioxide (SiO2)
mineral
Gold in Quartz
Gold (Au) in Silicon Dioxide (SiO2)
mineral
Quartz Vein in Matrix
Silicon Dioxide (SiO2) within Rhyolitic or Granitic Matrix
igneous
Quartz on Sandstone
Silicon Dioxide (SiO2) in Lithic Sandstone
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Fossilized shell or coral fragment
Indeterminate biogenic carbonate; likely calcite/aragonite (CaCO₃)
fossil
Gravel (mixed crushed stone)
Unidentified aggregate of crushed natural rock fragments
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Chalcedony with Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Cone-in-cone structure
Cone-in-cone structure
sedimentary
Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Gold Ore in Quartz
Auriferous Quartz (Au + SiO2)
igneous
Pyrite
Iron Sulfide (FeS2)
mineral
Fossilized Ripple Marks or Stromatolite
Sedimentary ripple mark imprint / Biosedimentary structure
fossil