Tumbled purple stone, likely charoite
Charoite, a complex potassium-calcium silicate mineral (commonly approximated as (K,Sr,Ba,Mn)₁₅–₁₆(Ca,Na)₃₂Si₇₀O₁₈₀(OH,F)₄·nH₂O)
metamorphic
Category
Mineralological Specimen
Browse mineralological specimen specimens identified by the Rock Identifier community.
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Quartz Pebble with Muscovite Mica
Quartz (SiO2) with Muscovite Mica (KAl2(AlSi3O10)(F,OH)2)
sedimentary
Schist (Micaceous Schist)
Mica Schist
metamorphic
Likely gneiss (dark, fine-grained specimen)
Foliated metamorphic rock, probably biotite–quartz–feldspar gneiss; exact identification requires closer examination
metamorphic
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Emerald in Matrix
Beryl (Be3Al2Si6O18)
mineral
Quartz-rich vein rock, possibly milky quartz with iron-oxide staining
Quartz (SiO₂), likely with limonite/goethite and minor host-rock material
mineral
Quartz geode fragment
Microcrystalline and drusy quartz, SiO₂, likely in a weathered carbonate or volcanic host
mineral
Milky quartz-bearing rock
Quartz, silicon dioxide (SiO₂), likely massive milky quartz in a host rock
mineral
Unidentified light-colored rock or mineral specimen
Indeterminate; possibly weathered calcite-rich material, limestone, or pale quartz-bearing rock
mineral
Small pale mineral fragment, possibly calcite
Unidentified; calcite (CaCO₃) is one possibility
mineral
Chert (Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz with Schist Matrix
Crystalline Silicon Dioxide (SiO2) in micaceous schist
metamorphic
Granite Pegmatite
Phaneritic Plutonic Igneous Rock
igneous
Mixed Rock and Mineral Collection
Various geological specimens
igneous, sedimentary, and metamorphic
Chert (Vuggy or Chalcedony)
Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz Druzy in Brecciated Matrix
Silicon Dioxide (SiO2) in Lithic Breccia
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Smoky quartz (likely)
Quartz, silicon dioxide (SiO₂)
mineral
Peridot (Olivine)
Magnesium Iron Silicate (Mg, Fe)2SiO4
mineral
River Rock (likely Gneiss or Quartzite)
Metamorphic rock specimen (potentially Foliated Gneiss)
metamorphic
Quartz Geode Fragment
Silicon Dioxide (SiO2)
mineral
Red Jasper (Chert)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Druzy Quartz on Agate/Chert
Silicon Dioxide (SiO2)
mineral
Jasper / Chert (river tumbled)
Microcrystalline Quartz (SiO2)
sedimentary
Galena with Pyrite on Matrix
Lead(II) sulfide (PbS) with Iron disulfide (FeS2)
mineral
Yellow Agate (Chalcedony)
Silicon Dioxide (SiO2)
mineral
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
sedimentary
Vein-filled Sedimentary Rock
Silicified sedimentary rock with quartz/calcite vein
sedimentary
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
mineral
Chert with Epidote and Jasper inclusions
SiO2 (Silicon Dioxide) with Ca2(Al, Fe)3(SiO4)3(OH) inclusions
sedimentary
Quartz / Calcite Vein Rock
Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)
mineral
Cullet Glass (Slag)
Amorphous Silicon Dioxide (Man-made)
Mineraloid
Mica-rich metamorphic rock, likely phyllite or mica schist
Quartz–muscovite phyllite/schist; commonly dominated by muscovite mica, quartz, and minor feldspar
metamorphic
Quartz–feldspar pegmatite with pink tourmaline
Granitic pegmatite; predominantly quartz (SiO₂), microcline/orthoclase (KAlSi₃O₈), albite (NaAlSi₃O₈), and likely elbaite tourmaline (Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
igneous
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
sedimentary
Crackle Agate / Dyed Quartz
SiO2 (Silicon Dioxide)
mineral
Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Pyrite
Iron Pyrite (FeS2)
mineral
Quartz-veined metamorphic rock, likely greenschist or altered metavolcanic
Chlorite–actinolite–epidote-bearing metavolcanic rock with quartz veins; exact identification requires testing
metamorphic
Fossil Assortment and Geological Specimens
Various (including Ammonoidea)
fossil