Man Made Material, Not A Natural Rock Or Mineral Specimen

Synthetic Resin (Artificial Specimen)

Polyurethane or Polyester Resin

Green Quartz / Chrysoprase / Sea Glass

Silicon Dioxide (SiO2)

Unidentified dark, flat specimen

Indeterminate; image resolution is insufficient for mineral identification

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Man-made Ceramic / Clay Figurine

Aluminosilicate Ceramic (Processed Clay)

Sandstone

Sandstone (SiO2 dominated)

Unknown dark mineral/rock fragment

Indeterminate; possibly a dark sulfide mineral or slag-like geological fragment

Ferrous Slag

Iron/Steel Slag (Complex Calcium-Alumino-Silicates)

Likely clear quartz crystal (possibly cut/polished quartz or glass imitation)

Quartz, silicon dioxide (SiO₂)

Polished brown chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂; iron oxides produce the brown coloration

Asphalt (Bituminous Concrete)

Composite material (bitumen binder with mineral aggregate)

Likely tumbled epidote-bearing rock or green jasper

Epidote-group silicate, possibly in a jasper or serpentinite matrix

Red-and-brown agate bead bracelet

Agate, a microcrystalline variety of quartz (SiO₂), likely colored chalcedony/carnelian

Sandstone (Quartzose Sandstone)

Arenite (SiO2 based)

White cabochon gemstone, likely milky chalcedony or opalite

Chalcedony: microcrystalline quartz, SiO₂; appearance may also indicate synthetic opalite glass

Colorless faceted quartz-like gemstone

Likely quartz (SiO₂), though the appearance may also indicate man-made glass or cubic zirconia

Iron-stained quartz-rich rock, possibly jasper or chert

Microcrystalline quartz (SiO₂) with iron oxides/hydroxides

Green Agate

Silicon dioxide (SiO₂)

Sandstone

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Lapis lazuli and green-blue chalcedony jewelry

Lapis lazuli: lazurite-bearing metamorphic rock, chiefly lazurite (Na₃Ca(Al₃Si₃O₁₂)S) with calcite and pyrite; second stone: likely chrysoprase or green-blue chalcedony (microcrystalline quartz, SiO₂)

Sandstone (Quartzite-rich Cobble)

Clastic sedimentary rock (primarily SiO2)

Diamond

Native Carbon (C)

Sandstone (likely Arkosic)

Clastic Sedimentary Rock (primarily SiO2 with Feldspar)

Diamond (as featured in jewelry)

Diamond (C - pure carbon)

Banded agate pendant (likely carnelian or brown-and-white chalcedony agate)

Agate, a banded variety of chalcedony; microcrystalline quartz, SiO₂, with iron-oxide coloration

Stainless Steel (Polished)

Ferrous Alloy containing Iron (Fe), Chromium (Cr), and Carbon (C)

Carved smoky quartz (likely)

Quartz, silicon dioxide (SiO₂), smoky variety

Polished dendritic agate or jasper pebble

Microcrystalline quartz (SiO₂), likely chalcedony with iron-oxide inclusions

Milky quartz (likely quartz crystal fragment)

Quartz, silicon dioxide (SiO₂)

Unidentifiable embedded dark fragment

Indeterminate; possibly a dark silicate mineral or lithic inclusion

Unknown brown-and-gold rock fragment

Undetermined; possibly iron-stained quartz, mica schist, or sulfide-bearing ore

Sandstone (likely Arkosic)

Arenite (SiO2 with KAlSi3O8)

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Iron-rich breccia or weathered ironstone

Goethite–hematite-bearing limonite, possibly with quartz and altered rock fragments

Quartz pebble in concrete

Quartz (SiO₂), embedded in Portland-cement concrete

Diamond

Diamond (Pure Carbon, C)

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (Lithic arenite / Quartz arenite)

Diamond

Carbon (C)

Natural Pearl

Calcium carbonate (primarily Aragonite and Conchiolin), CaCO3

Gemstone jewelry ensemble

Likely mixed gemstone and glass-bead jewelry; exact stones cannot be determined from the image

Chert

Silicon dioxide (SiO2)

Glass / Silicon Dioxide (Man-made)

SiO2 (Amorphous Silicon Dioxide)