Larimar
Pectolite (Sodium Calcium Silicate Hydroxide) - (NaCa2(Si3O8)(OH))
Mineral
Category
Basalt
Browse basalt specimens identified by the Rock Identifier community.
Greenschist
Greenschist facies rock
Metamorphic
Ruby in Zoisite
Ruby (Corundum, Al2O3) in Zoisite (Calcium aluminum silicate hydroxide, Ca2Al3(SiO4)3(OH)) with some Hornblende
Metamorphic Rock (specifically a rock composed of minerals)
Peridot
Olivine (Mg,Fe)2SiO4
Mineral
Peridot (Olivine)
Olivine, (Mg,Fe)2SiO4
Mineral
Agate (or Chalcedony)
SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz
Mineral
Banded Agate (variety of Chalcedony)
Agate (SiO2)
mineral
Larimar
Pectolite (a blue variety of Pectolite)
Mineral
Laterite
Laterite (primarily composed of hydrated oxides of iron and aluminum)
Sedimentary Rock (as a residual soil/rock, it's often considered a type of sedimentary rock due to its formation from weathering, though it can cross into soil science)
Pebble (river rock/beach pebble)
Pebble (clast size class)
Sedimentary Rock
Amethyst (Quartz)
SiO2 (Silicon Dioxide)
mineral
Amethyst
Amethyst (SiO₂)
Mineral
Sandstone (with potentially metamorphic or basaltic bands)
Arenite / Lithic Wacke
sedimentary
Quartz Vein in Host Rock (Gabbro or Basalt)
Silicon Dioxide (SiO2) with Mafic Silicates
metamorphic/igneous
Amphibolite
Amphibolite
metamorphic
Labradorite (likely Black Labradorite or Larvikite)
Labradorite (Na,Ca)(Al,Si)4O8. If a rock, it is typically anorthosite, gabbro, or norite, or a variety of syenite called Larvikite if it is specifically from Larvik, Norway.
Mineral/Igneous Rock
Chalcedony
Chalcedony (SiO₂)
Mineral
Magnetite
Magnetite (Fe3O4)
Mineral
Amethyst
Quartz (SiO2) with trace iron impurities
Mineral
Sapphire (Corundum)
Corundum (Al2O3), variety Sapphire
Mineral
Amethyst
Quartz (SiO2) with trace iron impurities
Mineral
Larimar
Pectolite (a variety of pectolite, NaCa2Si3O8(OH))
Mineral
Black Chert
Chert (microcrystalline quartz)
Mineral
Ruby
Corundum (Al₂O₃) with Chromium (Cr)
Mineral (gemstone)
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Mineral
Chalcedony Geode
Chalcedony (SiO2) within a geode structure
Mineral Geode/Sedimentary or Volcanic related
Banded Agate (likely Carnelian Agate or Sardonyx)
Agate is a common name for a microcrystalline variety of Quartz (SiO₂), specifically a form of Chalcedony.
Sedimentary Rock (technically a variety of Chalcedony)
Hypersthene
Hypersthene ((Mg,Fe)SiO₃)
Mineral
Amethyst
SiO2 (Silicon Dioxide) - a variety of Quartz
Mineral
Peridot and Citrine Gemstones (in a ring setting)
Peridot (Olivine: (Mg,Fe)2SiO4), Citrine (Quartz: SiO2)
mineral
Schist
Schist (various mineral compositions)
Metamorphic
Schist
Schist (various mineral compositions)
metamorphic
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Mineral
Amethyst
Quartz (SiO2) variety
Mineral
Agate (specifically, likely a geode slice or nodule)
Agate (a variety of Chalcedony, with chemical formula SiO2)
Mineral
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Mineral
Pumice
Pumicite (fine-grained pumice), Scoria (similar origin but denser and darker, usually basaltic)
Igneous
Blue Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz - SiO₂)
Mineral
Baroque Pearl (and potentially a small Sapphire/Blue Topaz)
Pearl: Calcium Carbonate (aragonite or calcite) with conchiolin. Sapphire: Aluminum Oxide (Al2O3). Blue Topaz: Al2SiO4(F,OH)2.
Organic Gemstone (for pearl), Mineral (for sapphire/topaz)
Serpentine
Serpentine group minerals (e.g., Antigorite, Chrysotile, Lizardite). Chemical formula: (Mg, Fe)₃Si₂O₅(OH)₄
Mineral, often found as a rock (metamorphic)
Gneiss (likely)
Gneiss
Metamorphic
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Mineral