Man Made

Cullet Glass (Slag)

Amorphous Silicon Dioxide (Man-made)

Green Sea Glass

Man-made silicate glass (weathered)

Libyan Desert Glass

Libyan Desert Glass (SiO2 with trace elements)

Weathered iron-rich concretion or ironstone nodule

Goethite–hematite limonite concretion (FeO(OH), Fe₂O₃, and hydrated iron oxides)

Mother of Pearl (Nacre)

Aragonite (CaCO3) with Organic Matrix

Black glassy fragment, likely obsidian or industrial glass

Volcanic glass (obsidian), chiefly amorphous SiO₂; identification uncertain from image

Red-orange cabochon, likely carnelian or glass imitation

Carnelian: chalcedony (microcrystalline SiO₂), commonly iron-colored

Clear quartz crystal

Quartz (silicon dioxide, SiO₂)

Not a rock, mineral, or geological specimen

Opalite

Synthetic glass / Opaque silicious glass

Tumbled quartz pebble

Quartz, silicon dioxide (SiO₂), likely milky quartz

Small greenish crystal/mineral fragment

Indeterminate; possibly olivine, quartz, or a green gemstone fragment

Dalmatian jasper

Porphyritic microcrystalline quartz-rich rock, commonly sold as Dalmatian jasper; spots are chiefly arfvedsonite/amphibole minerals, sometimes altered feldspar

Pyrite in Quartz (Drill Core)

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2) inclusions

Vesicular basalt (probable iron-rich volcanic rock)

Basalt; chiefly plagioclase, clinopyroxene, olivine, and Fe-Ti oxides

Polished milky quartz (likely quartz worry stone or wand)

Quartz, silicon dioxide (SiO₂)

White quartz pebble

Quartz (SiO₂), likely milky quartz

Polished black stone, likely black obsidian

Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)

Concrete Fragment

Artificial Conglomerate (Cement and Aggregate)

Metallic sulfide mineral fragment, likely galena

Galena (lead sulfide, PbS), tentative identification

Sea Glass

Silicon dioxide (mostly)

Bismuth

Bismuth (Bi)

Chert (Arrowheads)

Microcrystalline Quartz (SiO2)

Terrazzo (Man-made Composite)

Cementitious or Resin-bound Lithic Composite

Polished labradorite sphere

Labradorite, calcic plagioclase feldspar ((Ca,Na)(Al,Si)₄O₈)

Polished labradorite pendant

Labradorite, a calcium-rich plagioclase feldspar (approximately NaAlSi₃O₈–CaAl₂Si₂O₈)

Citrine Quartz

Citrine (Silicon Dioxide, SiO2)

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

Hematite

Iron(III) oxide (Fe2O3)

Concrete / Conglomerate (Man-made)

Artificial Conglomerate (Cementitious Composite)

Red-orange jasper pebble (tentative)

Microcrystalline quartz, SiO₂, colored mainly by iron oxides

Cobalt Blue Glass / Cullet Glass

Silicon dioxide (Amorphous man-made glass)

Opalite (Man-made Glass)

Synthetic Silicon Dioxide Glass (SiO2 + metal oxides)

Opalite-style pendant (likely synthetic glass, not natural opal)

Opalescent glass; commonly sold as “opalite” (not a recognized mineral species)

Magnetic Hematite (Man-made)

Iron Oxide (Fe2O3) with Barium-Strontium Ferrite

Stainless Steel (Polished)

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

Cubic Zirconia (Man-made)

Cubic Zirconia (ZrO2) with Enamel and Metal Alloy

Opalite (Man-made Glass)

Synthetic Opalised Glass

Opalite

Synthetic Opalite Glass / Opalized Glass

Asphalt Concrete

Bituminous conglomerate

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct