Man Made

Turquoise (likely stabilized or simulated Howlite)

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)

Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Weathered concrete or cementitious slab (not natural rock)

Artificial calcium-silicate cement composite; likely Portland cement concrete

Synthetic Convention Badge (Plastic/PVC)

Polyvinyl Chloride (PVC) / Polycarbonate

Green Aura Quartz

Silicon Dioxide (SiO2) bonded with metallic vapors (typically Gold, Chromium, or Titanium)

Red agate bead (likely dyed or treated)

Agate, a microcrystalline variety of quartz; SiO₂

White drusy quartz

Quartz, silicon dioxide (SiO₂), with a drusy coating of tiny crystals

Tumbled quartz (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Chert

Silicon Dioxide (SiO2)

Likely muscovite mica

Muscovite, KAl₂(AlSi₃O₁₀)(OH)₂

Likely chert (flint)

Microcrystalline quartz (SiO₂), likely chert; exact identification is uncertain from the image alone

Tumbled milky chalcedony (likely common opal or quartz-rich chalcedony)

Chalcedony, microcrystalline SiO₂; identification is uncertain from the photo

Tumbled yellow chalcedony (possibly citrine or pale agate)

Chalcedony, microcrystalline quartz (SiO₂); exact variety cannot be confirmed visually

Tumbled blue chalcedony (possibly blue agate)

Microcrystalline quartz, SiO₂; chalcedony variety

Chert (Flint)

Silicon dioxide (SiO2)

Diamond (or Diamond Simulant)

Carbon (C) or Cubic Zirconia (ZrO2)

Seashell Fragment

Calcium carbonate (CaCO3) - primarily Aragonite or Calcite

Diamond (Cut jewelry specimen)

Diamond (pure Carbon, C)

Ruby in Matrix

Corundum (Al2O3)

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Milky quartz pebble

Quartz, silicon dioxide (SiO₂)

Gold coin pendant on a chain

Gold (Au), likely a coin set in a gold-colored metal mount

Quartz geode with druzy crystals

Quartz (SiO₂), likely with iron-oxide staining and darker host rock

Diamond (Cut Gemstone)

Carbon (C)

Diamond (Cut and Polished)

Diamond (pure Carbon, C)

Diamond

Carbon (C)

Rough Sapphire (Corundum)

Corundum (Al2O3)

Pumice

Pumice (Vitreous volcanic rock)

Chert (specifically Flint Arrowhead)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Sea Glass

Anthropogenic Silicate Glass

Sea glass (likely pale blue glass)

Human-made silicate glass, likely soda-lime glass; not a natural mineral or rock

Likely rough green-blue glassy mineral fragment

Unidentified; the image is insufficient to distinguish a natural mineral from industrial slag or glass

Green sea glass (likely)

Anthropogenic glass, not a mineral; composition commonly soda–lime silicate glass

Gemstone ring (stones not reliably identifiable from the image)

Likely faceted yellow stones and clear stones set in a metal band; species and treatments are indeterminate visually

Orange glassy slag (industrial by-product)

Iron-rich silicate glass; composition varies, commonly Fe–Ca–Al silicate

Dyed Quartz Cube

Silicon Dioxide (SiO2)

Red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored chiefly by iron oxides

Yellow chalcedony (possibly iron-stained agate)

Microcrystalline quartz, SiO₂

Red jasper pebble

Jasper, an opaque, iron-oxide-colored variety of microcrystalline quartz (SiO₂)

Chalcedony (likely agate)

Microcrystalline quartz, SiO₂; agate is banded chalcedony

Granodiorite

Phaneritic Plutonic Intermediate-Felsic Rock

Colorless faceted gemstone, likely quartz

Quartz (SiO₂), tentative identification; the photo is insufficient to confirm the material