Mixed (Sedimentary, Igneous, And Metamorphic)

River Rocks (Polished River Pebbles)

Stream-rounded clastic sediments

Rock and Mineral Collection

Mixed Geological Specimens

Mixed Tumbled Gemstones and Minerals

Various silicate and oxide minerals

Mixed Rock Collection (Pebbles and Stones)

Various geological specimens

Tumbled Mixed Gemstones and Rocks

Various mineral species including quartz (SiO2) and silicate minerals

Mixed Mineral Collection

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

Gravel (Crushed Stone Aggregates)

Mixed Siliciclastic / Carbonate Aggregate

Mixed Tumbled Rocks and Minerals Collection

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

Mixed Tumbled Gemstones

Various silicate and oxide minerals

Granite or Granitic Gneiss

Granitoid / Gneiss

Mixed Mineral and Crystal Assortment

Various silicate and oxide minerals

Gravel / Crushed Stone

Aggregate (mixed mineral rock fragments)

Mossy Rock

Mixed lithology rock with Bryophyta (moss)

Faceted Gemstones (Mixed)

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

Educational Geologic Collection

Mixed Mineral and Rock Collection (Various compositions)

Exposed aggregate concrete (stone-chip surface)

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

Mixed tumbled rock and mineral collection

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

Migmatite

Migmatite (Mixed Rock)

Mixed River Pebbles

Clastic Sedimentary Alluvial Deposit / Polymictic Conglomerate Clasts

General Gravel (River Rock/River Stones)

Mixed Lithic Sediments (Conglomerate Clasts)

Mixed rock and mineral collection

Assorted geological specimens; individual species cannot be reliably identified from the image

Rounded quartz-rich river pebbles

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

Mixed Rock Collection

Polylithic Geological Specimen Mix

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 Rock and Mineral Collection

Multiple geological specimens

Decorative mosaic cross containing mixed rock and glass fragments

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

Asphalt aggregate

Human-made bituminous asphalt containing crushed silicate rock aggregate

Mixed Rock and Mineral Collection

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

River Pebbles and Quartz

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

Mixed Gemstone Bracelet

Mixed natural minerals and rocks (e.g., Rhodonite, Malachite, Sodalite, Rose Quartz, Black Tourmaline, Quartz/Chalcedony variants)

Quartz-rich rock, likely granite or quartz-bearing metamorphic rock

Undetermined; possibly granitic rock composed mainly of quartz and feldspar, with mica or other dark minerals

Beach Pebbles and Quartz Aggregates

Quartz pebbles and biogenic fragments (SiO2, CaCO3)

Mixed tumbled stones

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

Mixed river stones; foreground likely sandstone

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

Migmatite

Migmatite (Mixed metamorphic-igneous rock)

Mixed rock and mineral collection

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

Quartz-rich rock or quartz specimen

Quartz (SiO₂), likely massive quartz or quartz-bearing host rock

Road-surface aggregate (crushed stone)

Unidentifiable mixed lithic aggregate; likely basaltic/andesitic fragments with feldspar, quartz, and weathered rock

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Silver-colored mica schist

Muscovite–quartz schist, possibly with biotite

Mixed Rock and Mineral Collection

Various geological specimens