Man Made Material (Anthro Lithic Product)

Opalite

Synthetic Opalised Glass

Baked-clay ceramic fragment (likely brick or pottery)

Fired clay, primarily aluminosilicate minerals; not a natural rock

Conglomerate

Conglomerate Rock (Paraconglomerate)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Opalite

Synthetic Opalised Glass

Yellow cabochon gemstone, likely citrine or yellow glass imitation

Quartz (SiO₂), if natural citrine; visual evidence is insufficient to exclude man-made glass or resin

Blue glassy tumbled stone, likely blue chalcedony or slag glass

Chalcedony (microcrystalline SiO₂), possibly man-made blue glass

Green sea glass (likely bottle glass)

Man-made soda-lime silicate glass; not a natural mineral

Sea Glass

Amorphous Silicon Dioxide (Man-made glass weathered by nature)

Greywacke

Lithic Sandstone (Greywacke)

Chert (Arrowhead)

Chert (SiO2)

Jewelry Chain with Blue and Clear Gemstones (Likely Cubic Zirconia)

Cubic Zirconia (ZrO₂), Silver or White Gold/Platinum Alloy

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Titanium Amethyst Geode

Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer

Blue goldstone beads

Man-made aventurine glass (silica glass with metallic copper inclusions), not natural lapis lazuli

Fired Clay Brick (Anthropic Rock substitute)

Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)

Green Glass (often marketed as 'Obsidian' or 'Green Quartz')

Amorphous Silica (SiO2) with copper or chromium additives

Tuff with Quartz and Calcite Veining

Lithic Tuff (Silicified)

Hematite

Iron(III) oxide (Fe2O3)

Terrazzo (with Marble and Granite fragments)

Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates

Chert / Flint

Cryptocrystalline quartz (SiO2)

Polished green-and-black banded cabochon (likely malachite imitation or dyed agate)

Uncertain; possible malachite (Cu₂CO₃(OH)₂), banded agate (SiO₂), or man-made glass

Dyed Blue Agate (Dragon Vein Agate)

Silicon Dioxide (SiO2) with artificial cobalt/organic dyes

Diamond

Native Carbon (C)

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)

Granite with Cupules / Bedrock Mortars

Granite (felsic intrusive plutonic rock)

Carved Stone Turtle

Carved Soapstone and Quartz

Chert (Jasper)

Silicon dioxide (SiO2)

Chert (Flint)

Silicon dioxide (SiO2) - Cryptocrystalline Quartz

Small clear crystal, possibly quartz or glass-like gemstone

Uncertain; likely quartz (SiO₂), but the image is insufficient to exclude man-made glass or cubic zirconia

Opalite

Synthetic glass (SiO2 + metal additions)

Raw quartz crystal

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

Tumbled black stone, likely black obsidian

Obsidian; volcanic glass, typically rhyolitic composition (SiO₂-rich)

Dumortierite Quartz

Dumortierite in Quartz (Al6O3(BO3)(SiO4)3)

Metallic sulfide mineral fragment, likely galena

Galena (lead sulfide, PbS), tentative identification

Chert / Flint

Microcrystalline or cryptocrystalline Quartz (SiO2)

Blue tumbled glass-like specimen; likely blue slag glass

Likely man-made glass (silicate glass), not a natural mineral; exact material cannot be confirmed from the image

Carborundum (Silicon Carbide)

Silicon Carbide (SiC) / Moissanite (natural form)

Sandstone (Greywacke/Lithic Sandstone)

Arenite / Lithic Sandstone

Greywacke

Lithic Sandstone (Greywacke)

Milky quartz

Quartz, silicon dioxide (SiO₂)