Mixed: Igneous And Sedimentary

River Cobbles (Basalt, Quartzite, and Sandstone mix)

Fluvial detritus (primarily SiO2, Plagioclase, and Pyroxene mix)

Mixed Rock Collection (Pebbles and Stones)

Various geological specimens

Mixed Rock Collection

Polylithic Geological Specimen Mix

Tumbled Mixed Gemstones and Rocks

Various mineral species including quartz (SiO2) and silicate minerals

Granite or Granitic Gneiss

Granitoid / Gneiss

Mixed Mineral Collection

Multi-mineral Assemblage (Quartz, Jasper, Obsidian, Pyrite, etc.)

Dalmation Stone

Peralkaline Rock (mixed silicate minerals)

Gravel (Crushed Stone Aggregates)

Mixed Siliciclastic / Carbonate Aggregate

Quartz-rich rock fragment

Unidentified quartz–feldspar-rich rock; exact lithology cannot be determined from the image

Mixed Tumbled Rocks and Minerals Collection

Mixed Minerals and Rocks (Quartz, Feldspar, Jasper, Agate, Lapis Lazuli, Sodalite, Rose Quartz, Fluorite, etc.)

Rounded granitic pebble (likely granite or granodiorite)

Granite–granodiorite; chiefly quartz, feldspar, and mica/amphibole

Gravel / Crushed Stone

Aggregate (mixed mineral rock fragments)

Mossy Rock

Mixed lithology rock with Bryophyta (moss)

Mixed tumbled rock and mineral collection

Varied specimens, including probable quartz varieties, jasper, agate, fluorite, rose quartz, amethyst, pyrite, calcite, and others

Exposed aggregate concrete (stone-chip surface)

Portland-cement concrete containing natural aggregate; not a natural rock

Faceted Gemstones (Mixed)

Various (e.g., Corundum, Beryl, Quartz, or synthetic equivalents)

Granite or granitic gneiss pebble

Quartz–feldspar–mica aggregate; likely granite, possibly foliated gneiss

Mixed river stones; foreground likely sandstone

Quartz-rich sandstone, with associated rounded quartzite/chert and other cobbles

General Gravel (River Rock/River Stones)

Mixed Lithic Sediments (Conglomerate Clasts)

Educational Geologic Collection

Mixed Mineral and Rock Collection (Various compositions)

Mixed River Pebbles

Clastic Sedimentary Alluvial Deposit / Polymictic Conglomerate Clasts

Rounded quartz-rich river pebbles

Alluvial gravel; commonly quartzite, chert, and quartz-bearing sandstone fragments

River Pebbles and Quartz

Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)

Asphalt aggregate

Human-made bituminous asphalt containing crushed silicate rock aggregate

Dalmatian Stone (commonly called Dalmatian Jasper)

Peralkaline Rock (mixed Feldspar, Quartz, and Arfvedsonite)

Decorative mosaic cross containing mixed rock and glass fragments

Polychrome aggregate; likely quartz, feldspar, marble, granite, and assorted colored glass

Mixed Rock and Mineral Collection

Mixed Assemblage (includes Quartz, Jasper, Feldspar, and Turquoise-colored stones)

Mixed Rock and Mineral Collection

Various geological specimens

Blue Calcite (commonly sold as Caribbean Calcite)

Calcium Carbonate (CaCO3)

Concrete or asphalt-like aggregate surface with a dark fragment

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

Stream cobbles and gravel

Unidentified mixed fluvial clasts; likely quartzite, sandstone, and igneous/metamorphic fragments

Mixed Mineral and Rock Collection

Mixed geological specimens (Quartz, Amethyst, Rose Quartz, Jasper, Epidote, Chert)

Mixed mineral and rock collection

Predominantly quartz varieties, including amethyst, plus likely calcite, feldspar, mica, and miscellaneous polished stones

Amethyst and mixed gemstone bracelet

Amethyst: purple quartz, silicon dioxide (SiO₂); likely accompanied by other quartz or decorative mineral beads

Mixed tumbled stones

Mixed aggregate of quartz, chalcedony, jasper, feldspar, and other common silicate minerals

Mixed rock and mineral collection

Multiple specimens; visible pieces may include quartz, calcite, agate/chalcedony, jasper, and dyed or coated materials

Weathered volcanic rock fragment

Likely andesite or basaltic-andesite; exact identification requires fresh surface and testing

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Assorted Tumbled Gemstones

Mixed oxides and silicates (including Quartz, Chalcedony, and Feldspar variants)

Tumbled quartz-rich stone, possibly milky quartz or calcite

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

Fossil Assortment and Geological Specimens

Various (including Ammonoidea)

Conglomeratic concrete or asphalt aggregate surface with dark bituminous chunks

Polymictic gravel aggregate; dark pieces likely bitumen/asphalt, not a natural rock