Anthropogenic (Man Made Product Subject To Geological Processes)

Blue-green rough mineral specimen (identity uncertain)

Undetermined; the image is insufficient for a reliable mineral identification

Polished brecciated jasper

Jasper, microcrystalline quartz (SiO₂), likely brecciated and iron-oxide stained

Red jasper (likely polished/tumbled)

Jasper, an opaque microcrystalline variety of quartz/chalcedony (SiO₂), colored red by iron oxides

Brown iron-rich rock, likely limonite/goethite-bearing stone

Limonite (hydrated iron oxides; commonly goethite, FeO(OH), with hematite)

Iron-rich weathered pebble (likely limonite/goethite-bearing rock)

Limonite mixture, commonly dominated by goethite (FeO(OH)) and hematite (Fe₂O₃)

Quartzite

Metamorphic Quartzite (SiO2)

Quartzite Pebble

Quartzite (Metamorphosed Sandstone)

Sandstone

Arenite (primarily SiO2 with trace Fe2O3)

Hematite

Hematite (Fe2O3)

Polished jasper pebble

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored by iron oxides

Tumbled white stone, possibly milky quartz

Milky quartz (quartz, SiO₂), identification uncertain from image

Red garnet cabochon-style earrings

Likely almandine garnet (Fe₃Al₂(SiO₄)₃); the image alone cannot confirm the stone or whether it is natural or synthetic.

Gold-bearing Quartz Vein in Mafic Rock

Hydrothermal Quartz Vein within Greenschist/Amphibolite facies (SiO2 with Au)

Iron-stained chalcedony (possible agate/jasper)

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide staining

Tumbled carnelian (likely)

Carnelian, a reddish-orange variety of chalcedony; microcrystalline quartz (SiO₂)

Quartzite

Metamorphic Quartzite (SiO2)

Iron-rich weathered rock, possibly limonite/goethite-bearing ore

Limonite (hydrated iron oxides; chiefly goethite, FeO(OH), with hematite and other oxides possible)

Likely flint/chert fragments

Microcrystalline quartz (SiO₂), possibly fossil-bearing chert

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Small rounded pale stone

Indeterminate; likely quartz-rich pebble, possibly quartz or light-colored feldspar

Quartzite

Metamorphic quartz rock (SiO2)

Quartz-rich rock fragment (likely quartzite)

Quartzite, composed chiefly of quartz (SiO₂)

Banded calcite (onyx marble)

Calcite, CaCO₃; commonly sold as “honey onyx” or “Mexican onyx”

Mixed rock and mineral collection

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

Likely iron-rich quartzite or ironstone pebble

Quartz-rich rock with iron-oxide staining; exact identification requires examination

Tumbled carnelian (red-orange chalcedony)

Carnelian, a microcrystalline variety of quartz; SiO₂

Quartz

Silicon Dioxide (SiO2)

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Green-and-white marble (likely serpentine-bearing marble)

Calcite- or dolomite-rich marble with green serpentine/chlorite minerals; exact identification requires testing

Tumbled red-orange stone, likely carnelian

Carnelian, a translucent variety of chalcedony (microcrystalline quartz, SiO₂)

Quartzite

Metamorphic Quartzite (SiO2)

Quartzite

Metamorphic Quartzite (SiO2)

Coal

Bituminous or Anthracite coal (carbon-rich sedimentary rock)

Veined Quartz

SiO2 (Silicon Dioxide)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Milky Quartz

Silicon Dioxide (SiO2)

Fluorite

Fluorite (Calcium Fluoride, CaF2)

Polished pink-orange chalcedony (likely carnelian)

Microcrystalline quartz, SiO₂; carnelian is orange-red chalcedony

Quartzite

Metamorphic Quartz Arenite

Yellow agate or yellow chalcedony bead strand

Microcrystalline quartz (SiO₂), chalcedony; possibly iron-stained agate or heat-treated quartz

Tumbled jasper (likely)

Microcrystalline quartz, SiO₂; likely jasper, a variety of chalcedony

Limestone

Calcium Carbonate (CaCO3)