Gneiss
Gneiss (High-grade metamorphic rock)
Category
Browse mineral, often found as a rock (metamorphic) specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade metamorphic rock)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Blue Quartz (or Blue Aventurine)
Silicon Dioxide (SiO2) with inclusions (typically Crocidolite or Dumortierite)
Quartzite with Garnet inclusion
Metamorphic Quartz-rich Rock
Chert (Iron-stained or Dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Mudstone)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Black Chert (Flint)
Microcrystalline Quartz (SiO2)
Lapis Lazuli
Lapis Lazuli (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Quartzite with Dendritic Manganese Oxide Inclusions
Metamorphic Quartzite (SiO2 with Mn-oxides)
Greenstone (Prase / Nephrite / Serpentine mix)
Metamorphosed ultramafic rock / greenstone facies
Chert (often associated with Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Agate
Silicon Dioxide (Chalcedony), SiO2
Yellow Quartzite Pebble
Quartzite (primarily Silicon Dioxide - SiO2)
Gneiss
Gneiss (a type of metamorphic rock)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Shale (possibly Carbonaceous or Oil Shale)
Argillaceous Sedimentary Rock
Chert
Opaline or Microcrystalline Jasper/Chert (SiO2)
Quartzite River Rock
Quartzite (primarily SiO2)
Fulgurite
Fulgurite (Lechatelierite)
Epidote
Epidote (formula: Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Quartzite with Quartz Veining
Metamorphic Quartzite (SiO2)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within metamorphic/igneous matrix
Fulgurite
Fulgurite (Lechatelierite)
Limonite Concretion (Ironstone)
Limonite (FeO(OH)·nH2O) / Goethite
Pyrite in Host Rock
Iron Disulfide (FeS2)
Tiger's Eye (Brown/Dark variety)
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Green Aventurine in Host Rock
SiO2 (Quartz with Fuchsite inclusions)
Citrine Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz pebble with host matrix
Silicon Dioxide (SiO2)
Chert (Nodule)
Chert (Silica, SiO2)
Ruby (Raw Corundum)
Corundum (Al2O3 with Chromium impurities)
Banded Gneiss (River Cobble)
Gneiss (a high-grade metamorphic rock)
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Banded Chert
Chert (Microcrystalline Quartz, SiO2)