Igneous And Metamorphic Derivative (Weathered)

Rounded weathered pebble, likely granite or granitic gneiss

Probable granitoid: quartz, feldspar, and dark mica/amphibole

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Gold

Native gold (Au)

Gravel (Crushed Stone Aggregates)

Mixed Siliciclastic / Carbonate Aggregate

Quartz Pebble

Silicon Dioxide (SiO2)

Black Sand (Magnetite Sand)

Magnetite (Fe3O4)

Milky quartz

Quartz (silicon dioxide, SiO₂), likely a massive vein-quartz specimen

Biotite gneiss (probable)

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

Weathered granite or granitic gneiss cobble

Granite; primarily quartz, feldspar, and mica

Strawberry Quartz (Quartz with Hematite inclusions)

Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)

Cloudy Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Banded metamorphic rock, likely gneiss

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

Quartz-rich granitic pegmatite

Pegmatite, composed mainly of quartz (SiO₂), feldspar, and minor mica or iron-oxide minerals

Pyrite

Iron Sulfide (FeS2)

Likely serpentinite (serpentine-rich rock)

Serpentinite, composed mainly of serpentine-group minerals (e.g., antigorite, lizardite, or chrysotile)

Tumbled quartz pebble

Quartz, silicon dioxide (SiO₂)

Sandstone or Quartzite

Sandstone or Quartzite (SiO2 primarily)

Yellow Calcite

Calcium Carbonate (CaCO3)

Yellow Calcite

Calcium Carbonate (CaCO3)

Small quartz crystal (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Pyrite

Iron Sulfide (FeS2)

Weathered granite or granitic gneiss

Granite: quartz + feldspar + mica; possible gneissic variant

Weathered granite or granitic gneiss pebble

Granite; primarily quartz, potassium feldspar, plagioclase, and mica

Weathered granite or granitic gneiss boulder

Granite; predominantly quartz, feldspar, and mica (exact identification is uncertain from a photograph)

Likely banded gneiss or mica-rich metamorphic pebble

Gneiss; composition likely quartz, feldspar, and biotite/muscovite mica

Rounded dark stone, likely basalt or weathered mafic rock

Basalt (probable; mineral assemblage commonly plagioclase, pyroxene, and minor olivine)

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Veined basalt or dark mafic metamorphic rock

Basalt, likely altered and quartz/calcite-veined; exact identification requires testing

Milky quartz (rough fragment)

Quartz, silicon dioxide (SiO₂)

Tumbled white quartz (likely carved quartz pendant/bead)

Quartz, silicon dioxide (SiO₂)

Milky quartz pebble

Quartz, silicon dioxide (SiO₂)

Tumbled quartz-rich stone, possibly blue quartz or granite

Quartz (SiO₂), with probable feldspar and dark accessory minerals

Quartz Pebble (Sea Glass-like Quartz)

Quartz (Silicon Dioxide - SiO2)

Likely basalt or mafic metamorphic rock

Basalt, predominantly plagioclase feldspar and pyroxene; possibly metamorphosed to amphibolite

Weathered quartz-rich rock, possibly milky quartz or quartzite

Quartz (SiO₂), potentially quartzite if metamorphic

Likely weathered pink granite or feldspathic rock fragment

Granite, approximately quartz–feldspar–mica aggregate; exact identification is uncertain from the image

Likely weathered schist or gneiss fragment

Micaceous quartz-feldspar metamorphic rock; exact identification requires testing

Milky quartz in weathered host rock

Quartz, silicon dioxide (SiO₂), likely occurring in altered igneous or metamorphic matrix

Weathered dark volcanic rock, likely basalt

Basalt; fine-grained mafic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine and iron oxides

Weathered granite or granitic gneiss

Granite; mainly quartz (SiO₂), feldspar, and mica, possibly with metamorphic foliation

Quartz Pebble

Silicon Dioxide (SiO2)