Sedimentary And Igneous (Mixed)

Blue Calcite (commonly sold as Caribbean Calcite)

Calcium Carbonate (CaCO3)

Mixed rock and mineral collection

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

Mixed Mineral and Rock Collection

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

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)

Amethyst and mixed gemstone bracelet

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

Red Jasper

Silicon Dioxide with Iron Oxide inclusions (SiO2)

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

Iron-stained milky quartz

Quartz (SiO₂), with iron-oxide staining

Granite

Granite, a coarse-grained felsic intrusive igneous rock composed chiefly of quartz, feldspar, and mica or amphibole

Mixed Rock Collection

Polymineralic aggregate

Polished unakite pebble (likely)

Unakite: epidote, pink potassium feldspar, and quartz; composition varies

Mixed mineral and rock collection

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

Quartz (Moss-covered)

Silicon Dioxide (SiO2)

Mixed tumbled stones

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

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

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

Assorted Tumbled Gemstones

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

Fluorite

Calcium Fluoride (CaF2)

Tumbled quartz-rich stone, possibly milky quartz or calcite

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

Mixed Gemstone Bracelet

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

Conglomeratic concrete or asphalt aggregate surface with dark bituminous chunks

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

Fossil Assortment and Geological Specimens

Various (including Ammonoidea)

Mixed rounded river pebbles

Polymictic alluvial gravel; likely quartz/quartzite, chert, and weathered feldspathic rocks

Mixed rock and mineral specimen collection

Varied silicate, carbonate, and oxide minerals; individual identification is not possible from this group photograph

Gravel and Sand Aggregate

Unconsolidated Clastic Sediment

Mixed collection of natural stones

Several unidentified lithologies, likely including basalt, granite, quartzite, sandstone, and weathered metamorphic rocks

Mixed mineral and rock specimen collection with an obsidian-like centerpiece

Likely black obsidian (volcanic glass), alongside quartz, amethyst, agate/jasper, and other tumbled minerals

Mixed Rock Assortment

Polylithic geological specimens

Migmatite

Migmatite (Mixed Rock)

Mixed rock and mineral specimen collection

Mostly undetermined from the photograph; apparent quartz-rich rocks, sandstone, granite/gneiss, and possibly iron-oxide-bearing specimens

Mixed rock and mineral specimen collection

Multiple species, likely quartz (SiO₂), calcite (CaCO₃), feldspar, chert, and assorted volcanic/sedimentary rocks

River Pebbles (including Granite and Basalt)

Mixed Igneous Rocks (Granite, Basalt)

Granite with Pegmatite Dike

Felsic intrusive igneous rock

Quartz-rich rock or quartz specimen

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

Mixed Pebbles and Shell Fragments

Polylithic sedimentary aggregate and biogenic calcium carbonate

Mixed River Pebbles (including Unakite and Jasper)

Polymineralic geological specimens

Gravel or Crushed Stone

Fragmented Aggregate Stone

Mixed river-worn rock and mineral collection

Mostly quartz/quartzite, feldspar-bearing granitoid, chert, and mafic volcanic rocks; exact species vary by pebble

Mixed River Stones and Minerals

Mixed Silica-rich Stones (Quartz, Agate, Jasper, Sandstone, Dalmation Stone)