Man Made Silicate (Anthropogenic Glass)

Raw quartz crystal

Quartz (silicon dioxide, SiO₂), likely milky or included quartz

Cherry Quartz with Rose Quartz

Crystalline Quartz (SiO2) with glass-based synthetic components

Agate and millefiori glass jewelry

Agate: microcrystalline quartz (SiO₂); millefiori element appears to be man-made glass

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

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

Titanium Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Chert (Chalky Flint Node)

Chert (Microcrystalline Quartz, SiO2)

Obsidian (likely black volcanic glass)

Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Crackled Quartz (Blue Dyed)

Silicon Dioxide (SiO2) with anthropogenic dye

Fluorite (Polished Point/Tower)

Calcium Fluoride (CaF2)

Polished black pebble, possibly obsidian

Volcanic glass (obsidian), likely; identification is tentative from the image

Iron-rich slag or ironstone; appearance is not diagnostic

Likely iron-oxide-rich material (hematite, Fe₂O₃, and/or magnetite, Fe₃O₄); possibly smelting slag

Rainbow Hematite Ring

Iron(III) oxide (Fe2O3) with thin-film coating

Polymer Clay (Mock Mineral)

Polyvinyl chloride (PVC) with plasticizers and pigment

Concrete with Aggregate

Artificial Conglomerate (Cement and Aggregate)

Slag (Industrial Glass Slag)

Amorphous Silica / Ferro-silicate Slag

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Diamond / Clear Quartz / Glass paste

Carbon (Diamond) / Silicon Dioxide (Quartz)

Polished black stone, likely obsidian

Obsidian (volcanic glass; mostly silica-rich rhyolitic composition)

Goldstone (Brown/Gold variety)

Aventurine Glass (SiO2 with Copper inclusions)

Man-made Glass (Tumbled/Shaped)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Blue sea glass or blue glassy mineral fragment

Uncertain; likely man-made soda-lime glass, not a natural mineral

White pebble, likely quartz or calcite

Indeterminate from image; possible microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Cubic Zirconia (Jewelry Setting)

Zirconium Dioxide (ZrO2)

Diamond

Native Carbon (C)

Conglomerate

Conglomerate (clastic sedimentary rock)

Green glassy mineral fragment, possibly fluorite

Fluorite (calcium fluoride, CaF₂), tentative identification

Cubic Zirconia (Jewelry Setting)

Cubic Zirconia (ZrO2)

Dzi Bead (Etched Chalcedony)

Cryptocrystalline Quartz (SiO2) with chemical etching

Milky quartz (rough fragment)

Quartz, silicon dioxide (SiO₂)

Polished white calcite sphere (identification tentative)

Calcite, CaCO₃

Blue glassy fragment among beach gravel

Likely cobalt-blue man-made glass; not a natural mineral specimen

Green Slag Glass

Amorphous Silica Glass (Anthropogenic)

Likely clear quartz crystal or glass-like gemstone

Quartz, silicon dioxide (SiO₂); exact identification is uncertain from the strongly magenta-lit image

Concrete-like aggregate surface with embedded rock fragments

Anthropogenic concrete or exposed aggregate; not a natural rock specimen

Sea Glass (Frosted Glass Fragment)

Amorphous Silica (Anthropogenic Sediment)

Carborundum (Silicon Carbide)

Silicon Carbide (SiC)

Titanium Aura Quartz

Silicon Dioxide (SiO2) coated with Titanium and Niobium

Concretion with Geode Cavity

Ferruginous Sandstone Concretion with Quartz Center

Concrete fragment or Conglomerate

Artificial Conglomerate (Concrete) or Natural Conglomerate

Dalmatian Stone

Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)

Red-orange cabochon, likely carnelian or glass imitation

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

Tumbled black obsidian (likely)

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