Man Made Glass (Often Grouped With Minerals In Lapidary)

Dyed Crackle Quartz (Green)

Quenching-treated Quartz (Silicon Dioxide, SiO2)

Blue Goldstone

Aventurine Glass (SiO2 with Cobalt/Copper inclusions)

Cubic Zirconia (Jewelry Setting)

Zirconium Dioxide (ZrO2)

Concrete

Anthropogenic Sedimentary Conglomerate (Cement mixture: typically Ca2SiO4, Ca3SiO5, Ca3Al2O6)

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

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

Chalcedony on Matrix

Silicon Dioxide (SiO2)

Blue Cracked Quartz (Dyed Fire Crackle Quartz)

Silicon Dioxide (SiO2) with synthetic dye

Clay (as a rock-forming material)

Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)

Glass / Silicon Dioxide (Man-made)

SiO2 (Amorphous Silicon Dioxide)

Ocean Jasper Mushroom

Orbicular Jasper (Silicon Dioxide, SiO2 mixed with various impurities)

Sandstone Anvil / Nutting Stone

Quartzose Sandstone (Sedimentary Rock)

Sea Glass

Man-made silicate glass (Amorphous silicon dioxide)

Silicon Carbide (Carborundum)

Silicon Carbide (SiC) / Moissanite (natural)

Green Quartzite

Metamorphic Quartzite (often colored by chromium-bearing minerals or fuchsite)

Sea Glass

Man-made silicate glass weathering product

Chert Concretion (with typical hematite/limonite staining)

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

Sandstone-based Concrete Fragment

Cementitious Composite with Sedimentary Aggregate

Concrete with Exposed Aggregate

Anthropogenic conglomerate (Concrete)

Cobalt Glass Slug (Man-made Glass)

Amorphous Silica with Cobalt Oxide (SiO2 + CoO)

Goldstone

Aventurine Glass (Man-made glass with copper inclusions)

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Transit Token (RTD Denver)

Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)

Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (Chert or Flint)

Carved Mottled Greenish-Yellow Crystal/Glass Object

Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.

Red Sandstone or Brick Fragment

Arenite (if sandstone)

Concrete / Anthropogenic Conglomerate

Man-made composite material (Portland cement, aggregate, and water)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Nickel coin (U.S. currency)

Cupronickel (75% Copper, 25% Nickel alloy)

Dyed Aura Quartz

Silicon Dioxide (SiO2) with metallic coating

Concrete fragment with Aggregate

Anthropogenic Concrete with Calcarious and Siliceous Aggregate

Opalite

Synthetic Glass (Amorphized Silicon Dioxide)

Sea Glass

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

Aura Quartz (Rainbow Quartz)

Silicon Dioxide (SiO2) with metallic vapor coatings

Polished brown jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide and other mineral inclusions

Blue goldstone beads

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

Slag Glass (Cullet)

Amorphous Silica / Glass residue

Cubic Zirconia (Jewelry Setting)

Cubic Zirconia (ZrO2)

Carborundum

Silicon Carbide (SiC)

Cullet (Slag Glass)

Amorphous Silica (Industrial byproduct)

Green Sea Glass

Amorphous Silica (man-made glass), SiO2 + additive metal oxides

Libyan Desert Glass

Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)

Orthoclase Feldspar (Sunstone variety)

KAlSi3O8 (Potassium Aluminum Silicate)