Synthetic (Man Made Material Mimicking Natural Stone)

Faceted purple-blue beads, likely synthetic glass or treated gemstone

Indeterminate; possible synthetic corundum, synthetic spinel, or dyed quartz (SiO₂)

Sea Glass

Man-made vitreous material (silica-based glass)

Slag

Metallurgical by-product

Pearls (likely freshwater cultured pearls)

Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin

Gastropod Internal Mold (Steinkern)

Class Gastropoda fossil mold (Phylum Mollusca)

Blue Impression Jasper beads

Impression jasper (microcrystalline quartz/chalcedony), chiefly SiO₂, with iron-oxide and other mineral inclusions

Rainbow Hematite Ring

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

Cubic Zirconia (as used in jewelry setting)

Zirconium dioxide (ZrO2)

Yellow faceted gemstone earrings, likely citrine or yellow beryl

Citrine: quartz, SiO₂; possible yellow beryl: Be₃Al₂Si₆O₁₈

Diamond

Carbon (C)

Diamond

Carbon (C)

Quartzite (or Engineered Quartz Stone)

SiO2 (Silicon Dioxide)

Exposed aggregate concrete (stone-chip surface)

Portland-cement concrete containing natural aggregate; not a natural rock

Aura Quartz

Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)

Polished milky quartz (likely quartz worry stone or wand)

Quartz, silicon dioxide (SiO₂)

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

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

Colorless faceted gemstone, likely cubic zirconia

Cubic zirconia (zirconium dioxide, ZrO₂); visual confirmation is unavailable

Asphalt Chunk

Asphalt concrete

Slag Glass (Leland Blue variant)

Anthropogenic Vitreous Silicate

Concrete with Aggregate

Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)

Sandstone (with concrete/human-made layer)

Clastic Sedimentary Rock (primarily Quartz/Feldspar grains)

Cullet Glass (Slag)

Amorphous Silicon Dioxide (Man-made)

Yellow-orange faceted gemstone, likely citrine or yellow topaz

Citrine: quartz, SiO₂; yellow topaz: Al₂SiO₄(F,OH)₂

Porcelain Tile (Sandstone-look)

Man-made Ceramic (resembling Quartz-rich Sandstone)

Granite with Cupules / Bedrock Mortars

Granite (felsic intrusive plutonic rock)

Pink Quartz / Sea Glass

Silicon Dioxide (SiO2)

Red synthetic corundum (ruby-colored lab-grown sapphire)

Corundum, aluminum oxide (Al₂O₃), likely synthetic and chromium-colored

Chert Concretion (with typical hematite/limonite staining)

Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)

Dyed Quartz Geode

Silicon Dioxide (SiO2) with artificial pigment

Peridot gemstone pendant

Olivine, gem-quality forsteritic olivine (approximately (Mg,Fe)₂SiO₄)

Sea Glass

Amorphous silicon dioxide (SiO2) - Man-made glass tumbled by nature

Goldstone

Aventurine Glass (SiO2 + Cu small inclusions)

Sandstone Concretion

Limonitic Sandstone Concretion

Clear Quartz (Faceted) or Cubic Zirconia / Glass imitation

SiO2 (if Quartz), ZrO2 (if Cubic Zirconia)

Diamond

Native Carbon (C)

Diamond (or Diamond Simulant)

Carbon (C) if diamond, various if simulant

Blue Goldstone

Aventurine Glass (Silicon Dioxide infused with Cobalt/Copper)

Zinc Alloy (Silver-plated)

Zinc Alloy Casting (Zn-Al-Mg-Cu)

Libyan Desert Glass

Libyan Desert Glass (SiO2 with trace elements)

Strawberry Quartz (or Sunstone / Tumbled Quartz)

Silicon Dioxide (SiO2) with Hematite/Lepidocrocite inclusions

Faceted pale-green gemstone, likely prasiolite or green quartz

Quartz (SiO₂), likely prasiolite; identification is uncertain from the photograph

Carborundum (Silicon Carbide)

Silicon Carbide (SiC) / Moissanite (natural form)