Industrial Byproduct

Obsidian (likely black volcanic glass)

Obsidian; mostly amorphous SiO₂-rich rhyolitic glass

Baroque cultured pearl necklace

Pearl: nacre composed mainly of aragonite (CaCO₃) and conchiolin

Pearl necklace (likely cultured pearls)

Pearl; chiefly aragonite (CaCO₃) in an organic conchiolin matrix

Polished brecciated jasper pebble

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with contrasting mineral-filled fractures

Tumbled orange calcite

Calcite (CaCO₃)

White quartz bead strand

Quartz, silicon dioxide (SiO₂), likely milky or translucent quartz; beads are polished and drilled

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.

Dalmatian jasper (polished stone beads)

Commercial “Dalmatian jasper”; typically a feldspar-rich rock with dark aegirine or arfvedsonite inclusions, not true jasper

Ruby (cushion-cut red gemstone)

Corundum, Al₂O₃; red color is typically caused by chromium

Gemstone ring with dark blue cabochons

Likely blue sapphire (corundum, Al₂O₃); the stones cannot be identified confidently from the image

Polished brecciated jasper (likely)

Brecciated jasper, an opaque microcrystalline quartz (SiO₂) with contrasting silica-rich fragments and matrix

Rounded pebble, likely fine-grained river stone

Unidentified lithic pebble; composition cannot be determined from the image

Unidentified brown stone

Indeterminate from the image; possibly a common iron-stained mineral or rock fragment

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

Likely polished or naturally smoothed pebble with a pale mineral patch

Undetermined; possibly a dark volcanic rock with a quartz or feldspar inclusion

Quartz cabochon ring (stone identity uncertain)

Quartz, SiO₂ (possible smoky or included quartz)

Unidentified small mineral specimen

Undetermined from the image

Fossil brachiopod

Brachiopoda; likely a spiriferid or strophomenid brachiopod

Ruby (Raw Corundum)

Al2O3 (Aluminum Oxide)

Quartz (Milky or Iron-stained)

Silicon Dioxide (SiO2)

Sandstone (Quartzite-rich)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone

Arenite (SiO2 primarily)

Native Copper with Malachite/Oxide Coating

Native Copper (Cu)

Diamond (or Diamond Simulant)

Carbon (C) if diamond, various if simulant (e.g., Cubic Zirconia ZrO2)

Quartz Vein Rock

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Polished banded stone, likely zebra jasper

Zebra jasper (banded microcrystalline quartz, chiefly SiO₂, with iron-oxide and carbonate impurities)

Limestone Cobble

Carbonate Rock (CaCO3)

Sandstone Pebble

Arenite (SiO2 based)

Sandstone with Iron Staining

Arenite (SiO2 with Fe-oxide impurities)

Mixed Mineral Collection (Quartz, Amethyst, Rose Quartz, Pyrite, etc.)

Mixed Silicates and Sulfides (SiO2, FeS2)

Vuggy Quartz / Chert

Silicon Dioxide (SiO2)

Yellow Quartz

Silicon Dioxide (SiO2)

Coal (Bituminous Coal)

Caustobiolith / Sedimentary Rock

Quartz Matrix with Iron Staining / Mica Schist

Silicon Dioxide (SiO2) with Iron Oxide staining

Quartz Pebble

Silicon Dioxide (SiO2)

Corundum (Sapphire in Matrix)

Aluminum Oxide (Al2O3)

Quartz (Agate/Chalcedony)

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (Chalcedony), SiO2

Garnet

Garnet Group (e.g., Almandine Fe3Al2(SiO4)3 or Pyrope Mg3Al2(SiO4)3)

Garnet

Garnet Group (Silicate Minerals)

Garnetiferous Quartzite (Garnet Gneiss Pebble)

Garnet-bearing Quartzite or Quartz-Feldspar Gneiss