Jade (Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)
Category
Browse igneous or metamorphic specimens identified by the Rock Identifier community.
Jade (Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)
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.
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety, likely a orthogneiss or paragneiss depending on parent rock)
Eclogite
Eclogite (Omphacite + Pyrope)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Epidote in Matrix (likely Amphibolite or Gneiss)
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Metamorphic Matrix
Quartz vein in metamorphic rock
Crystalline Silicon Dioxide (SiO2) in Host Rock
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Almandine Garnet in Schist
Almandine, Fe3Al2(SiO4)3
Smoky Quartz
SiO2 (Silicon Dioxide)
Amethyst
Quartz (SiO2) variety
Garnet (likely Almandine or Pyrope)
Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2AlSi3O10(OH)2
Mica Schist with Quartz
Mica-Quartz Schist (Muscovite subclass)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Gold
Aurum (Elemental Gold, Au)
Orthoclase Feldspar
Potassium aluminum silicate (KAlSi3O8)
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Eclogite
Eclogite (Pyrope garnet and Omphacite pyroxene)
Unakite
Unakite (Epidotized Granite)
Slate
Slate
Schist
Mica Schist
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite with Quartz Vein
Quartzite (primarily SiO2)
Mixed collection of minerals and rocks (Jasper, Carnelian, Granite, and Quartz)
Silicon Dioxide (SiO2) with varying impurities for silicates and igneous aggregates
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Quartz (Float/Abraded)
Quartz (SiO₂)
Pyrite
Iron Pyrite (FeS2)
Fluorite Bracelet (light green beads) and possibly Lavender Jadeite (purple bead)
Fluorite: CaF₂ (Calcium Fluoride); Jadeite: NaAlSi₂O₆ (Sodium Aluminum Silicate)
Peridot (Olivine)
Olivine ((Mg,Fe)2SiO4)
Mica Schist
Mica Schist (predominantly Muscovite or Biotite)
Rhodonite
Rhodonite (MnSiO3)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Banded Gneiss
Gneiss (pronounced "nice")
Biotite Schist (with Garnet and Pyrite)
K(Mg,Fe)3AlSi3O10(OH,F)2 (Biotite focus)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate)
Garnet (Almandine)
Almandine, Fe3Al2Si3O12
Fuchsite
Chrome-bearing Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2]
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.