Mixed (Igneous, Sedimentary, Metamorphic, And Minerals)

Weathered limestone or calcareous concretion

Calcite-rich limestone; predominantly calcium carbonate (CaCO₃)

Crushed Stone (Gravel/Aggregates)

Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)

Mixed rock and mineral collection

Mixed lithologies; likely quartz, feldspar, basalt, granite, chert, sandstone, and metamorphic rocks

Smoky Quartz with Feldspar

SiO2 (Quartz) with KAlSi3O8 (Feldspar)

Mixed rounded fieldstones, likely granite and gneiss

Granite (quartz–feldspar–mica) and gneiss; exact identification is uncertain from the photograph

Quartz with Chlorite / Greenschist

Quartz vein in Greenschist (SiO2 with Chlorite group minerals)

Quartz-rich metamorphic rock, likely mica schist

Mica schist; chiefly quartz (SiO₂) and mica, likely muscovite/biotite, with possible feldspar

Weathered conglomeratic volcanic rock

Likely basaltic volcanic breccia or agglomerate, with plagioclase, pyroxene, volcanic glass, and lithic fragments

Gneiss (likely garnet-bearing)

Banded orthogneiss/paragneiss; chiefly quartz, feldspar, biotite and amphibole, with possible garnet

Mixed polished gemstone and mineral collection

Primarily quartz varieties (SiO₂), plus probable aventurine, rose quartz, amethyst, agate, jasper, serpentine, feldspar, and possibly dyed or man-made glass pieces

Pink Granite

Granite (Phaneritic Acidic Igneous Rock)

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Granite fragment

Granite, chiefly quartz (SiO₂), feldspar, and mica

Granite Pebble

Granite

Unidentified gravel and stone fragments

Mixed, indeterminate lithologies; likely quartz, feldspar, and weathered silicate rock fragments

Granite pebble

Granite; primarily quartz, alkali feldspar, plagioclase, and dark mica/amphibole

Mixed mineral and rock collection, including likely amethyst and assorted tumbled stones

Unidentified mixed specimens; visible purple quartz is likely amethyst (SiO₂)

Lapis Lazuli

Lapis Lazuli (Rock containing lazurite, calcite, and pyrite)

Gray granite or granitic gneiss gravel

Granite; primarily quartz, feldspar, and mica (exact identification is uncertain from the photograph)

Asphalt Concrete

Bituminous Concrete (Anthropic Rock)

Magnetite

Magnetite (Fe3O4)

Gravel or Pebble

Clastic Sedimentary Grain (typically composed of Quartz or Silicate minerals)

Kaolin (China Clay)

Kaolinite [Al2Si2O5(OH)4]

Quartz

Silicon Dioxide (SiO2)

Assorted polished river pebbles

Mixed lithologies, likely quartzite, chert, jasper, and weathered igneous/metamorphic rocks

Quartz

Silicon Dioxide (SiO2)

Quartz (Tumbled)

SiO2 (Silicon Dioxide)

Quartz (Citrine or Iron-Stained)

SiO2

Quartz with Iron Staining

Silicon Dioxide (SiO2) with Hematite/Limonite inclusions

Siltstone

Siltstone (composed of mixed silicate minerals and clay)

Mixed collection of tumbled minerals and rough specimens

Multiple species visible; likely fluorite, quartz/chalcedony, pyrite, tiger’s eye, rose quartz, and possibly labradorite or agate

Mixed gemstone specimens

Likely pink sapphire or tourmaline, red garnet, blue sapphire, precious opal, and green tourmaline/emerald; exact identities cannot be confirmed from the collage

Granite

Granite (Phaneritic intrusive igneous rock)

Pyrite in Matrix (Healers Gold / Pyrite Egg)

Iron Disulfide (FeS2) with Magnetite/Hematite matrix

Coarse sand with a small pebble

Unconsolidated siliciclastic sediment, chiefly quartz and rock fragments

Mixed polished and tumbled mineral specimens, prominently amethyst

Amethyst: purple quartz, SiO₂; accompanying pieces may include jasper, agate, aventurine, tiger’s eye, and other lapidary stones

Polished/rounded granite cobble

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

Garnet crystals

Garnet-group silicates, likely almandine (Fe₃Al₂Si₃O₁₂)

Quartz-rich pegmatite, with probable feldspar and mica

Granite/pegmatite assemblage: quartz (SiO₂), feldspar (KAlSi₃O₈–NaAlSi₃O₈–CaAl₂Si₂O₈), and mica

Blue Calcite (commonly sold as Caribbean Calcite)

Calcium Carbonate (CaCO3)

Weathered granite

Granite, a coarse-grained felsic intrusive igneous rock

Coarse-grained igneous rock, likely granitic pegmatite or weathered granite

Granite/pegmatitic granite; chiefly quartz (SiO₂), feldspar, and dark mica or amphibole