Man Made Byproduct (Non Geological)

Quartzite River Cobble

Quartzite (SiO2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Stone bead bracelet

Unidentified polished natural-stone beads; possibly wood-grain jasper, agate, or serpentine

Chert (varietal Chalcedony or Flint)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Diorite

Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)

Rounded brown river pebble

Indeterminate lithic fragment; possibly weathered sandstone, mudstone, or basalt

Porous limestone (likely fossiliferous or weathered limestone)

Calcite-rich limestone; chiefly calcium carbonate (CaCO₃)

Likely tumbled green aventurine or serpentine

Aventurine quartz (SiO₂ with fuchsite mica) or serpentine-group mineral

Fossilized Bored Limestone

Limestone with Ichnofossils (Gastrochaenolites or Entobia)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sea Shell (Fighting Conch Fragment)

Calcium Carbonate (CaCO3) - Strombus alatus fragment

Anthracite Coal

Anthracite

Green aventurine bead bracelet

Quartz (SiO₂), typically green aventurine containing fuchsite mica or other chromium-bearing inclusions

River Pebble (likely Quartzite or Diorite)

Metamorphosed Quartz-rich Rock / Intermediate Igneous Rock

Greenstone / Glauconitic Siltstone

Metabasalt or Glauconite-rich Sedimentary Rock

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

Pyrite

Iron Sulfide (FeS2)

Shale (with Iron Staining)

Argillaceous mudstone / Shale

Small tumbled brown stone, likely iron-stained quartz or jasper

Quartz (SiO₂) or microcrystalline quartz (chalcedony/jasper), identification uncertain from the image

Mixed beach-stone and tumbled-glass collection

Predominantly uncertain rocks (likely basalt, granite, and quartz-bearing stones) with anthropogenic glass; one possible banded agate or jasper

Weathered polymictic gravel/conglomeratic rock

Polymictic conglomerate or poorly lithified alluvial gravel; chiefly quartz, feldspar, mica, and dark lithic fragments

Quartzite

Quartzite (Primary mineral: SiO2)

Rounded sandstone pebble

Clastic sandstone, predominantly quartz (SiO₂) grains in a cementing matrix

Weathered limestone with possible fossil or calcite coating

Limestone; primarily calcium carbonate (CaCO₃), chiefly calcite

Polished black stone carving, likely soapstone/steatite

Steatite (massive talc), Mg₃Si₄O₁₀(OH)₂; exact material cannot be confirmed from the image

Quartz (likely Chalcedony or Chert)

Silicon Dioxide (SiO2)

Beaded gemstone bracelet, likely lapis lazuli and pale quartz/agate

Lapis lazuli: lazurite-rich rock, chiefly (Na,Ca)₈(AlSiO₄)₆(S,SO)₂; pale beads are uncertain

Polished agate geode slice

Microcrystalline quartz (chalcedony), SiO₂

Crinoid Fossil Stem Segment

Class Crinoidea (Echinodermata)

Rounded quartz pebble

Quartz (silicon dioxide, SiO₂)

Diorite (River Pebble)

Intermediate plutonic igneous rock

Emerald and diamond ring

Emerald: beryl, Be3Al2Si6O18, colored green by chromium and/or vanadium; surrounding stones appear to be diamonds, crystalline carbon (C)

Chert

Microcrystalline Quartz (SiO2)

Rounded iron-rich stone or concretion

Indeterminate; possibly hematite-/goethite-bearing sandstone or an ironstone concretion

Anthracite

Anthracite Coal

Diorite

Diorite

Obsidian

Obsidian (Volcanic Glass, complex silicate)

Chert

Microcrystalline quartz (SiO2)

Limonite or Ironstone Nodule

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)

Polished orbicular jasper

Jasper, microcrystalline quartz (SiO₂), with iron oxides and other inclusions

Black Obsidian

Volcanic Glass (SiO2)

Black tourmaline pendant

Schorl tourmaline, NaFe3Al6(BO3)3Si6O18(OH)4