Hematite (beads)
Hematite (Fe₂O₃)
Mineral
Category
Metamorphic Or Igneous Alteration
Browse metamorphic or igneous alteration specimens identified by the Rock Identifier community.
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Mineral, specifically a detrital grain
Quartz
Quartz (SiO₂)
Mineral
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Metamorphic Rock
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Mineral
Blue Quartz
Quartz (SiO2) with inclusions
Mineral
Laterite
Laterite (no specific mineral formula as it's a rock type)
Sedimentary
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
Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Amazonite
Amazonite (KAlSi3O8, a variety of Microcline)
Mineral
Quartz (likely)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
Quartz with Mica/Chlorite inclusions
Silicon Dioxide (SiO2) with phyllosilicate inclusions
igneous/metamorphic mineral specimen
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Banded Gneiss (Variety of Gneiss)
Gneiss (specifically, a variety exhibiting prominent banding; mineral composition can vary, but often contains quartz, feldspar, mica, and amphibole)
Metamorphic Rock
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Rock (likely Sedimentary)
Yellow Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)
Mineral
Smoky Quartz
SiO2 (Silicon Dioxide)
Mineral
Aventurine (likely Green Aventurine)
Silicon Dioxide (SiO2) with various inclusions
Mineral, variety of Quartz
Amethyst
Quartz (SiO2) variety
Mineral
Garnet (likely Almandine or Pyrope)
Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)
Mineral
Citrine
SiO2 (Silicon Dioxide)
Mineral
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Mineral, Sediment
Quartz (Float/Abraded)
Quartz (SiO₂)
Mineral
Strawberry Quartz
Silicon Dioxide (SiO2) with inclusions of Goethite or Hematite
Mineral
Pyrite
Iron Pyrite (FeS2)
mineral
Fluorite Bracelet (light green beads) and possibly Lavender Jadeite (purple bead)
Fluorite: CaF₂ (Calcium Fluoride); Jadeite: NaAlSi₂O₆ (Sodium Aluminum Silicate)
Mineral for Fluorite; Mineral/Rock for Jadeite (as it's often a rock composed primarily of jadeite mineral)
Peridot (Olivine)
Olivine ((Mg,Fe)2SiO4)
Mineral
Quartz (in matrix)
Quartz (SiO₂)
mineral
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)
Metamorphic Rock
Gold
Aurum (Elemental Gold, Au)
Mineral, Metal (element)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Mineral
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Man-made Object (Metal/Alloy)
Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)
Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates
igneous, sedimentary, and metamorphic
Gneiss
Gneiss (pronounced 'nice')
Metamorphic Rock
Smoky Quartz
SiO2 (Silicon Dioxide)
Mineral
Citrine
Quartz (SiO₂) variety
Mineral
Quartz (Crystal/Druzy Quartz)
Quartz (SiO₂)
Mineral
Milky Quartz
Quartz (SiO₂)
Mineral
Amazonite
KAlSi3O8 (Potassium Feldspar, variety of Microcline)
Mineral