Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Metamorphic Rock
Category
Mineral Health
Browse mineral health specimens identified by the Rock Identifier community.
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Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Devil's Toenail (Fossil Oyster)
Gryphaea arcuata (Calcium Carbonate, CaCO3)
sedimentary
Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
mineral
Limonite Stained Basalt
Hydrated Iron Oxide on Mafic Volcanic Rock (FeO(OH)·nH2O)
igneous
Quartz (Water-worn pebble)
Silicon Dioxide (SiO2)
mineral
Quartz Mineral
Silicon dioxide (SiO2)
mineral
Pyrite in Quartz
Iron Sulfide (FeS2) in Silicon Dioxide (SiO2)
Mineral
Fluorite
Calcium fluoride (CaF2)
mineral
Granite Cobble
Granite
igneous
Limonite (Ironstone)
Limonite (FeO(OH)·nH2O)
mineral
Fluorite (Rainbow, Purple-Blue Tumbled)
Calcium Fluoride (CaF2)
Mineral
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz on Schist
Silicon Dioxide (SiO2) on Foliated Metamorphic Rock
metamorphic
Blue Apatite
Apatite - Ca5(PO4)3(F,Cl,OH) (Calcium phosphate with Fluorine, Chlorine, or Hydroxyl)
mineral
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Granite
Granite (Phaneritic Quartz-Feldspar Plutonic Rock)
igneous
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Basalt with Amygdule
Aphanitic Mafic Volcanic Rock (Basalt) with Zeolite/Quartz Infill
igneous
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Extrusive volcanic rock)
igneous
Banded Gneiss
Gneiss (typically quartz, feldspar, mica, amphibole composition)
metamorphic
Milky Quartz with Mineral Inclusions
Quartz (Silicon Dioxide, SiO2)
mineral
Fluorite
Calcium fluoride, CaF2
Mineral
Gneiss
Metamorphic Gneiss (High-grade regional metamorphism)
metamorphic
Gneiss
Gneiss (Metamorphic rock)
metamorphic
Granitic Gneiss
Gneiss (Metamorphic rock of granitic composition)
metamorphic
Granite
Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)
igneous
Mixed Gemstone and Mineral Collection
Mixed Silica and Carbonate minerals (SiO2, CaSO4·2H2O, etc.)
mineral
Fluorite Tower
Fluorite (Calcium Fluoride - CaF2)
mineral
Sandstone with Manganese Dendrites
Clastic Sedimentary Rock (SiO2 based with MnO2 inclusions)
sedimentary
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Yellow Ochre / Limonite
Hydrated ferric oxide (FeO(OH)·nH2O)
mineral
Sandstone (with Limonite staining)
Arenite (primarily SiO2 with FeO(OH)·nH2O)
sedimentary
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Turquoise
Turquoise, CuAl6(PO4)4(OH)8·4H2O
mineral
Garden Quartz (Lodalite)
Silicon Dioxide with various mineral inclusions (SiO2)
mineral
Schist
Schist (various mineral compositions)
Metamorphic
Gneiss (foliated metamorphic rock)
Gneiss
metamorphic
Morganite and Aquamarine (Beryl) Bracelet
Beryllium aluminum silicate, Be3Al2(SiO3)6
gemstone