Quartz (Milky Quartz vein fragment)
Silicon Dioxide (SiO2)
mineral
Category
Sedimentary Rock
Browse sedimentary rock specimens identified by the Rock Identifier community.
Pyrite
Pyrite (Iron Disulfide), FeS2
Mineral
Blue Quartzite
Quartzite (specifically a variety enriched with blue-coloring minerals)
Metamorphic Rock
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
igneous
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Ruby in Zoisite
Ruby (α-Al2O3) embedded in Zoisite (Ca2Al3(SiO4)3(OH)) with some Hornblende
Metamorphic Rock (composed of multiple minerals)
Chalcedony (Agate/Jasper mix in host rock)
Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)
mineral
Pink Granite
Phaneritic Felsic Igneous Rock (Granite, rich in Potassium Feldspar)
igneous
Carnelian (Chalcedony variety)
SiO2 (Silicon Dioxide)
Mineral
River Stone (likely Basalt or Chert)
Silicon Dioxide (SiO2) for chert or Mafic Extrusive Rock for basalt
igneous/sedimentary
Note: Item is not a geological specimen
n/a
none
Note: No specimen visible
N/A
Jasper in Basalt Matrix
Silicon Dioxide (SiO2) with impurities; Chalcedony
sedimentary (secondary mineral) within igneous
Wishing Stone with Quartz Veins
Quartzite or Quartz-veined Metamorphic Rock (composed mainly of SiO2)
metamorphic
Granite Pebble
Granite (composition of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Man-made Object (Metal/Alloy)
Shatter Cone
Impactite (Shatter Cone texture)
metamorphic
Massive Quartz (Milky or Gray)
Silicon Dioxide (SiO2)
mineral
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Mineral
Ocean Jasper
Silicon Dioxide (SiO2) with various inclusions
igneous/sedimentary mixed (Orbicular Jasper)
Halite
Halite (NaCl)
Mineral
Amber (Cherry or Red variety)
Succinite (with various trace amounts of organic compounds)
Organic Gemstone (not a rock)
Moonstone
Orthoclase Feldspar (KAlSi3O8)
mineral
Brecciated Jasper
Silicon Dioxide (SiO2) with varying mineral inclusions (Iron Oxide, Hematite, Clay)
sedimentary (clastic/chemical)
Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)
Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.
Metamorphic, Mineral (within a rock type)
Diorite (possibly fine-grained variety or a related intermediate intrusive rock like a felsic gabbro or a dark granodiorite)
Diorite (Igneous rock, intrusive, intermediate composition)
Igneous Rock
Quartz (likely milky/gray variety)
Quartz (SiO₂)
Mineral
Banded Gneiss
Gneiss (pronounced "nice")
metamorphic
Basalt (Amygdaloidal)
Amygdaloidal Basalt
igneous
Lapis Lazuli (blue bead) and Moss Agate (green heart)
Lapis Lazuli (lazurite-based rock) and Moss Agate (SiO2 with manganese/iron inclusions)
metamorphic (Lapis) and sedimentary/igneous assoc. (Moss Agate)
Agate (various color varieties)
SiO₂ (Silicon Dioxide)
Mineral (specifically a variety of Chalcedony, which is a microcrystalline quartz)
Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Granite Cobble
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Basalt with Plagioclase Feldspar
Basalt (mafic extrusive igneous rock) with plagioclase feldspar phenocrysts
Igneous
Banded Agate (Polished Slice)
Chalcedony (cryptocrystalline Quartz), SiO2
mineral
Quartz Geode/Cluster
Quartz (SiO2)
mineral
Kyanite
Kyanite (Al2SiO5)
Mineral
Agate
Silicon Dioxide (SiO2)
mineral
Massive Quartz with Host Rock
Silicon Dioxide (SiO2)
mineral
Turritella Agate (Elimia Agate)
Silicified Elimia tenera (formerly misidentified as Turritella)
sedimentary (silicified fossiliferous chalcedony)
N/A - Non-Geological Item
not a rock/mineral
Basalt with Quartz Veining
Basalt (Mafic Extrusive Igneous Rock) with SiO2 (Silicon Dioxide) veins
igneous