Sedimentary Or Igneous Fragment

Granite or granitic rock fragment

Granitic rock, chiefly quartz, feldspar, and mica

Quartz Crystal Fragment

Silicon Dioxide (SiO2)

Quartz crystal fragment

Quartz, silicon dioxide (SiO₂)

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Quartz Crystal (Geode Fragment)

Silicon Dioxide (SiO2)

Massive White Quartz

Silicon Dioxide (SiO2)

Weathered quartz-rich metamorphic rock (probable gneiss or quartzite)

Biotite–quartz–feldspar gneiss, possibly micaceous quartzite

Sedimentary Pebble

Sedimentary Rock Fragment

Quartz (Milky/Clear Fragment)

Silicon Dioxide (SiO2)

Clear Quartz Fragment

Quartz (Silicon Dioxide, SiO2)

Weathered quartz-rich rock fragment

Likely quartz-bearing sandstone or granitic rock; exact identification is uncertain from the image

Granite fragment

Granite; mainly quartz (SiO₂), feldspar, and mica

Sand and Gravel (Quartz-rich)

Unconsolidated fluvial/beach sediment (primarily Silica/SiO2)

Rough garnet-bearing metamorphic rock

Likely garnet amphibolite or garnet-bearing schist; garnet-group silicate, commonly almandine (Fe₃Al₂Si₃O₁₂)

Quartz Geode

Crystalline Silicon Dioxide (SiO2) in Geode form

Quartz Druzy (on Geode Fragments)

Silicon Dioxide (SiO2)

Quartz / Common Gravel

Silicon Dioxide (SiO2)

Garnet-bearing metamorphic rock, likely garnet gneiss or garnet amphibolite

Garnet-bearing gneiss; red crystals likely almandine garnet, Fe₃Al₂(SiO₄)₃

Quartz Vein in Schist

Quartz-rich Micaceous Schist (SiO2 + phyllosilicates)

Fossilized bone fragment (probable mammalian tooth or bone)

Mineralized bone, commonly hydroxyapatite [Ca5(PO4)3(OH)] replaced or impregnated by silica/calcite

Likely quartz fragment

Quartz (silicon dioxide, SiO₂), possibly milky quartz or quartz-rich rock

Tumbled green aventurine

Quartzite dominated by quartz (SiO₂), commonly containing fuchsite mica or chlorite

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Likely weathered granite or granitic pegmatite fragment

Granite; chiefly quartz (SiO₂), feldspar, and mica/amphibole

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Chalcedony (Agate/Chert variety)

Silicon Dioxide (SiO2)

Quartz-rich sandstone or granitic fragment

Likely quartz–feldspar sandstone; exact identification is uncertain from the photograph

Dark gneiss or banded metamorphic rock

Banded quartz–feldspar–mica gneiss; exact identification requires testing

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Sedimentary Rock (Limestone or Siltstone pebble)

Sedimentary rock fragment

Weathered dark stone, possibly basalt

Basalt; commonly plagioclase feldspar, pyroxene, and minor olivine

Likely garnet-bearing metamorphic rock

Garnet amphibolite or garnet-bearing schist; chiefly almandine garnet (Fe₃Al₂Si₃O₁₂) with amphibole, mica, and quartz

Fossilized shell fragment

Indeterminate fossil mollusk; likely a silicified or mineral-replaced bivalve/gastropod fragment

Likely quartz-rich stone or shell fragment

Uncertain; possibly quartz (SiO₂) or a calcareous shell fragment (CaCO₃)

Biotite-rich schist (likely mica schist)

Mica schist; predominantly quartz, biotite mica, and feldspar

Fluorite

Calcium Fluoride (CaF2)

Mica Schist fragment

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3(AlSi3O10)(OH)2)

Quartz Crystal Fragment

Silicon Dioxide (SiO2)

Weathered granite fragment

Granite, chiefly quartz, potassium feldspar, plagioclase, and biotite/hornblende

Likely weathered quartz-bearing rock (uncertain identification)

Possibly quartz-rich granite or granitic aplite; exact identification requires a clearer, larger image and tests

Weathered quartz-rich metamorphic rock, likely gneiss or schist

Quartz–feldspar–mica gneiss/schist (tentative; image resolution limits certainty)

Likely quartz fragment

Quartz (silicon dioxide, SiO₂)