Unknown (Likely Sedimentary Or Metamorphic)

Zebra Jasper (with Chlorite/Epidote)

Silicon Dioxide (SiO2) with inclusions

Banded gneiss

Gneiss, commonly quartz–feldspar–mica gneiss

Weathered quartzite cobble

Quartzite, predominantly crystalline SiO₂

Polished magnetite-rich rock, likely magnetite-bearing schist or ironstone

Magnetite (Fe₃O₄) in a foliated silicate matrix; exact identification requires testing

Rounded tan cobble, likely quartzite or sandstone

Quartzite (mostly quartz, SiO₂); possibly quartz-rich sandstone

Gneiss (with Quartz-Feldspar vein)

Gneiss (high-grade metamorphic rock) containing Quartz (SiO2) and Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8)

Weathered quartz-rich cobble (likely quartzite)

Quartzite; predominantly microcrystalline quartz (SiO₂)

Pyrite-bearing rock (likely pyrite-rich quartz or schist)

Pyrite, FeS₂, intergrown with quartz and/or mica-rich matrix

Tumbled gneiss or granitic gneiss pebble

Quartz–feldspar–mica gneiss; composition typically quartz, plagioclase/alkali feldspar, and biotite or hornblende

Dyed, polished stone—possibly rhodonite or pink jasper

Likely rhodonite (MnSiO₃) or manganese-rich jasper; exact identification requires testing

Likely quartz-rich stone, possibly milky quartz

Quartz (silicon dioxide, SiO₂)

Quartz-rich river pebble, possibly weathered quartzite

Quartzite; predominantly crystalline SiO₂, though exact identification is uncertain from the photograph

Fossilized shell fragment, likely bivalve

Bivalvia indet.; commonly preserved as calcite (CaCO₃) shell material

Shale or slate fragment

Fine-grained phyllosilicate rock, likely slate (metamorphosed shale)

Gneiss, likely migmatitic or granitic gneiss

Banded quartz–feldspar–mica gneiss; composition chiefly quartz, alkali/plagioclase feldspar, biotite and accessory minerals

Garnet–biotite schist (likely garnetiferous mica schist)

Garnet-bearing mica schist; chiefly quartz, biotite/muscovite, feldspar, and almandine-pyrope garnet

Tumbled milky quartz (probable)

Quartz, silicon dioxide (SiO₂)

Tumbled red jasper with a quartz vein

Jasper (microcrystalline quartz, SiO₂), likely crossed by milky quartz

Slate or fine-grained shale

Slate; predominantly quartz, mica, and clay-derived minerals

Weathered quartz-rich metamorphic rock, likely quartzite

Quartzite, predominantly crystalline SiO₂, possibly micaceous or feldspathic

Weathered quartz-rich rock, likely sandstone or quartzite

Quartz arenite (sandstone) or quartzite; predominantly SiO₂

Weathered gneissic metamorphic rock

Gneiss, likely quartz–feldspar–mica gneiss

Biotite-bearing gneiss or schist

Quartz–feldspar–mica metamorphic rock, likely mica schist/gneiss

Pyrite-bearing schist or quartzite

Micaceous quartz-rich metamorphic rock with pyrite (FeS₂)

Banded limestone or marble

Calcite-rich carbonate rock; likely veined limestone, possibly low-grade marble (CaCO₃)

Gneiss with a polished reddish-brown stone

Banded granitoid gneiss; the foreground pebble may be jasper or iron-rich quartzite

Pyrite-bearing schist (likely gold-colored mica, not native gold)

Muscovite–quartz schist with pyrite; muscovite KAl₂(AlSi₃O₁₀)(OH)₂, pyrite FeS₂

Quartzite Geode (unopened)

SiO2 (Silicon Dioxide)

Pink Gneiss / Pink Granite Gneiss

Felsic Gneiss (dominated by Orthoclase Feldspar and Quartz)

Weathered quartz-rich cobble (probable quartzite or silicified rock)

Quartzite, predominantly SiO₂; exact identification is uncertain from the photograph

Pyrite in Matrix (likely Quartz or Schist matrix)

Iron Sulfide (FeS2)

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Banded gneiss

Foliated silicate rock, typically quartz–feldspar–mica gneiss

Epidote–garnet schist (probable)

Epidote + garnet + quartz/feldspar mica schist; garnet may be almandine–grossular series

Polished brecciated jasper

Microcrystalline quartz (SiO₂), commonly with hematite/goethite and iron-rich alteration minerals

Banded gneiss (likely amphibolite-rich gneiss)

Banded gneiss; composition commonly quartz, feldspar, mica and/or amphibole

Likely graphite-rich schist or graphite-bearing metamorphic rock

Graphite (C) in a mica/quartz-rich matrix; exact rock name requires testing

Gneiss (likely Granitic Gneiss)

Gneiss

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Weathered schist or gneiss fragment

Quartz–feldspar–mica metamorphic rock; likely mica schist or gneiss

Quartz (likely milky/rose quartz variety)

Quartz (SiO2 - Silicon Dioxide)

Banded gneiss pebble

Gneiss, commonly quartz–feldspar–mica gneiss