Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Mineral
Category
Igneous Or Metamorphic
Browse igneous or metamorphic specimens identified by the Rock Identifier community.
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Rose Quartz
Quartz (SiO2) with trace elements of titanium, iron, or manganese
mineral
Smoky Quartz
SiO2 (Silicon Dioxide)
mineral
Aventurine (Green Aventurine)
Quartz with Fuchsite Inclusions (SiO2)
Mineral
Smoky Quartz
SiO2 (Silicon Dioxide)
Mineral
Mixed Gemstone Beaded Jewelry
Various minerals (e.g., Quartz varieties like Rose Quartz, Amethyst; Peridot; Garnet; etc.)
Mineral
Hypersthene
Hypersthene ((Mg,Fe)SiO₃)
Mineral
Chalcopyrite
Chalcopyrite (CuFeS2)
Mineral
Moonstone
Orthoclase Feldspar (specifically showing adularescence)
Mineral
Quartz (beads)
SiO2 (Silicon Dioxide)
Mineral
Calcite
Calcite (CaCO₃, Calcium Carbonate)
Mineral
Green Aventurine
Aventurine (a variety of Quartz, SiO2)
Mineral
Moss Agate
Moss Agate (a variety of Chalcedony, SiO ₂)
Mineral (specifically a variety of Chalcedony, which is microcrystalline Quartz)
Limonite (Iron Ore/Hydrated Iron Oxide)
Limonite (mixture of FeO(OH)·nH₂O minerals, mainly Goethite, FeO(OH) and Lepidocrocite, FeO(OH))
Mineral
Citrine
Quartz (SiO2) - variety Citrine
Mineral
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Mineral
Biotite Mica
K(Mg,Fe)3AlSi3O10(OH)2
Mineral in a matrix (likely quartz or feldspar)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Mineral
Pegmatite (likely Granitic Pegmatite)
Pegmatite (a coarse-grained igneous rock, often with granitic composition)
igneous
Bi-Color Tourmaline (or Watermelon Tourmaline)
Tourmaline (complex borosilicate mineral group with general formula AD3G6(BO3)3T6O18(OH,O)4)
Mineral
Strawberry Quartz
Silicon Dioxide (SiO2) with inclusions of Goethite or Hematite
Mineral
Aventurine (likely Green Aventurine)
Silicon Dioxide (SiO2) with various inclusions
Mineral, variety of Quartz
Yellow Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)
Mineral
Citrine
SiO2 (Silicon Dioxide)
Mineral
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)
Aventurine (likely Green Aventurine)
Aventurine (a variety of quartz, SiO₂, with common inclusions of fuchsite)
Mineral/Metamorphic Rock
Quartz
SiO₂ (Silicon Dioxide)
Mineral
Mixed collection of common river stones
Varied lithologies, visibly including quartz-rich rock, dark mafic rock, sandstone, and purple quartz-bearing material
igneous, sedimentary, metamorphic
Smoky Quartz
Smoky Quartz (SiO2)
Mineral
Mixed river stones and gravel
Polymictic alluvial clasts; individual pieces may include quartzite, granite, basalt, sandstone, limestone, and slate
igneous, sedimentary, metamorphic
Smoky Quartz
SiO2 (Silicon Dioxide)
Mineral
Citrine
Quartz (SiO₂) variety
Mineral
Rose Quartz
Rose Quartz (SiO2)
Mineral
Orange Calcite
Calcite (CaCO3)
Mineral
Magnetic Hematite
Magnetized Hematite (an iron oxide mineral, Fe2O3, that has undergone magnetization)
Mineral
Strawberry Quartz
Quartz (SiO₂) with Goethite (α-FeO(OH)) and/or Lepidocrocite (γ-FeO(OH)) inclusions
Mineral
Beryl (Variety Mix)
Be3Al2(Si6O18)
Mineral
Sapphire
Corundum (Al₂O₃) with trace elements causing color variations.
Mineral
Calcite
Calcite (CaCO3)
Mineral
Mixed stream gravel and common rock specimens
Predominantly quartz-rich granitoid, quartzite, sandstone, shale/slate, and mafic volcanic fragments; exact species cannot be determined confidently from the image
igneous, sedimentary, metamorphic
Assorted Beach Rocks and Pebbles
Various (Granite, Basalt, Quartz, Conglomerate, etc.)
igneous, sedimentary, metamorphic
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Sedimentary Rock