Gneiss Pebble
Gneiss
Category
Browse igneous or sedimentary specimens identified by the Rock Identifier community.
Gneiss Pebble
Gneiss
Milky Quartz
Silicon Dioxide (SiO2)
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
Veined Quartz
SiO2 (Silicon Dioxide)
Quartz (likely Yellow/Orange variety, possibly Citrine or Chalcedony with iron staining)
Quartz (SiO₂)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Hematite (Iron Ore)
Hematite (Fe2O3)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Carnelian Agate
Silicon dioxide (SiO2) - variety of Chalcedony
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz (Crystal Cluster)
Silicon Dioxide (SiO2) - Quartz Variety
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartz (likely tumbled or naturally water-worn)
Quartz (SiO₂ - Silicon Dioxide)
Quartz (specifically Milky Quartz/Quartzite)
Silicon Dioxide (SiO2)
Folded Schist / Gneiss (Metamorphic Rock)
Regional Metaphoric Folded Outcrop (predominantly Schist/Gneiss)
Quartz
Quartz (SiO₂)
Quartz (possibly milky quartz)
Quartz (Silica; SiO₂)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Pyrite
Iron Sulfide (FeS2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Carnelian Agate
Carnelian (Silicon Dioxide: SiO2) with iron oxide impurities
Black Obsidian and Hematite
Volcanic Glass (SiO2) and Hematite (Fe2O3)
Gneiss
Gneiss
Hematite
Iron(III) oxide (Fe2O3)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartz (Milky Quartz)
Quartz (SiO2 - Silicon Dioxide)
Garnet (likely Almandine or a blend)
Garnet group: X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+. Given the dark, somewhat reddish-brown appearance in the image, it's likely Almandine (Fe3Al2(SiO4)3) or a mix with other iron-rich garnets.
Quartz (likely Milky Quartz)
Quartz (SiO₂ - Silicon Dioxide)
Quartz (various varieties)
SiO₂ (Silicon Dioxide)
Banded Agate (specifically Botryoidal/Orbicular Agate)
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
White Quartz
Quartz (SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Granitic Gneiss
Gneiss (high-grade metamorphic rock primarily of quartz, feldspar, and mica)
Graphite
Graphite (C)