Igneous Or Sedimentary

Carnelian

Silicon dioxide (SiO2) with iron oxide impurities

Concrete or asphalt-like aggregate surface with a dark fragment

Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock

Banded gneiss

Foliated, banded gneiss; typically composed of quartz and feldspar with mica or other dark minerals

Banded gneiss pebble

Gneiss, chiefly quartz–feldspar–mica; exact variety indeterminate from image

Rounded metamorphic cobble, likely gneiss or amphibolite

Banding-free biotite–quartz–feldspar gneiss or amphibolite; exact identification requires testing

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss

Gneiss

Granite / Gneiss (Felsic Metamorphic or Igneous Rock)

Gneiss (or weathered Granite)

Banded Gneiss

Gneiss (Metamorphic rock)

Coarse-grained metamorphic rock, likely gneiss or schist

Probable biotite-quartz-feldspar gneiss/schist; exact identification requires a fresh surface and tests

Banded metamorphic rock, likely gneiss

Foliated gneiss; chiefly quartz, feldspar, and dark mica/amphibole

Quartz Druzy

Crystalline Silicon Dioxide (SiO2)

Green Fluorite

Calcium Fluoride (CaF2)

Epidote

Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

Gneiss

Metamorphic Gneiss (High-grade regional metamorphism)

Gneiss (Metamorphosed Pebble)

Gneiss with Quartz/Feldspar banding

Banded gneiss

Gneiss, likely biotite–quartz–feldspar gneiss

Carnelian

Carnelian (a variety of Chalcedony); SiO2 (Silicon Dioxide)

Polished banded stone, likely gneiss or metasedimentary rock

Banded gneiss (quartz–feldspar–mica assemblage; exact identification requires testing)

Gneiss

Metamorphic Gneiss

Gneiss (Banded Gneiss)

Gneiss

Quartz (Crystalline Cluster)

Silicon Dioxide (SiO2)

Banded gneiss pebble

Gneiss, likely quartz–feldspar–mica gneiss

Banded Gneiss with Quartz Vein

Gneiss containing SiO2 (Quartz) intrusion

Gneiss

Gneiss

Gneiss

High-grade Metamorphic Gneiss

Gneiss (High-Grade Metamorphic Rock)

Gneiss (primarily composed of Quartz, Feldspar, and Mica/Amphiboles)

Gneiss

Gneiss (Metamorphic high-grade)

Polished banded gneiss pebble

Gneiss, commonly quartz–feldspar–biotite gneiss

Banded metamorphic rock, likely gneiss or banded amphibolite

Undetermined foliated metamorphic rock; commonly quartz–feldspar–biotite gneiss or amphibolite

Carnelian

Silicon Dioxide (SiO2) - variety of Chalcedony

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Likely raw garnet fragment

Garnet-group silicate, commonly almandine (Fe₃Al₂Si₃O₁₂)

Chalcedony (Agate/Carnelian precursor)

Chalcedony (Silicon Dioxide, SiO2)

Biotite-bearing gneiss

Mica gneiss, composed mainly of quartz, feldspar, and biotite mica

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Banded gneiss (likely weathered paragneiss)

Gneiss; quartz–feldspar–mica ± amphibole assemblage

Banded Gneiss

Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Biotite/Amphiboles)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Nuummite

Nuummite (Orthoamphibole rock / Anthophyllite-Gedrite blend)