Granite Pebble
Granite
igneous
Category
Mineral Health
Browse mineral health specimens identified by the Rock Identifier community.
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Red Granite Pebble
Intrusive Felsic Igneous Rock (Granite)
igneous
Granite Pebble
Intrusive Igneous Rock (Granite)
igneous
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Diorite
Phaneritic Intermediate Igneous Rock
igneous
Granite
Granite (Felsic Plutonic Rock)
igneous
Gneiss
Metamorphic Gneiss (High-grade regional metamorphism)
metamorphic
Amygdaloidal Basalt with Agate/Zeolite Amygdules
Basalt (extrusive igneous rock) containing secondary mineral fillings
igneous
Cubic Zirconia (Faceted)
Zirconium dioxide (ZrO2)
mineral
Banded Gneiss
Gneiss (typically quartz, feldspar, mica, amphibole composition)
metamorphic
Rock Specimen
Unclassified rock specimen
sedimentary
Limonite (Ironstone) pseudomorph
Limonite (Hydrous ferric oxide), FeO(OH)·nH2O
mineral
Calcite
Calcite (Mineral; CaCO₃)
Mineral
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Small pink mineral fragment
Indeterminate; possibly rose quartz or feldspar
mineral
Milky quartz
Quartz (silicon dioxide, SiO₂)
mineral
River Stones (Quartzite and Sandstone)
Quartzite / Sedimentary Rock (SiO2 dominant)
sedimentary
Ironstone concretion (possibly pyrite-bearing)
Iron-rich sedimentary concretion, likely composed of goethite/limonite with possible pyrite
sedimentary
Likely pegmatite with quartz and mica
Granitic pegmatite, chiefly quartz (SiO₂), feldspar, and mica
igneous
Purpurite
Purpurite (MnPO4)
mineral
Tumbled amethyst
Quartz, SiO₂; purple color typically from trace iron and natural irradiation
gemstone
Purple druzy quartz (likely dyed or coated)
Quartz, SiO₂ (trigonal crystal system)
mineral
Tumbled amethyst
Quartz, SiO₂; purple coloration from trace iron and natural irradiation
mineral
Amethyst (likely tumbled or polished)
Quartz, SiO₂; purple color commonly caused by trace iron and natural irradiation
mineral
Yellow Quartz
Silicon Dioxide (SiO2)
mineral
Diamond (or Cubic Zirconia simulant)
C (Carbon) or ZrO2 (Zirconium Dioxide)
gemstone
Polished orbicular jasper (likely ocean jasper)
Silica-rich microcrystalline quartz/chalcedony with iron oxides and accessory minerals; SiO₂-dominant
mineral
Weathered basalt pebble
Basalt, a fine-grained mafic volcanic rock; likely olivine- and pyroxene-bearing
igneous
Vein-bearing metamorphic rock, likely gneiss or schist
Banded silicate rock; likely quartz–feldspar–mica gneiss with a quartz vein
metamorphic
Vesicular basalt (likely weathered lava rock)
Vesicular basalt; primarily plagioclase feldspar, pyroxene, and volcanic glass, with possible iron-oxide alteration
igneous
Limonite / Ironstone
Hydrated Iron Oxide (FeO(OH)·nH2O)
mineral
Granite (likely a granitic rock)
Granite, composed chiefly of quartz, feldspar, and dark mica or amphibole
igneous
Likely amphibolite
Amphibolite, composed mainly of hornblende (amphibole) and plagioclase feldspar
metamorphic
Green-speckled igneous rock, likely epidote-bearing basalt or serpentinite
Tentatively epidote-bearing basalt (compositionally uncertain from the image)
igneous
Shark Tooth Fossil
Carcharocles megalodon or similar extinct shark tooth
fossil
Mica schist (likely biotite–muscovite schist)
Mica schist; chiefly quartz and mica minerals (muscovite KAl₂(AlSi₃O₁₀)(OH)₂ and/or biotite)
metamorphic
Snowflake Obsidian
Obsidian with Cristobalite inclusions
igneous
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Milky quartz fragment
Quartz, silicon dioxide (SiO₂)
mineral
Blue Apatite
Apatite (Ca5(PO4)3(F,Cl,OH))
mineral
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral