Man Made Material (Anthropogenic 'Mineraloid')

Man-made Green Quartz (Lab-grown or Treated)

Silicon Dioxide (SiO2) with artificial coloration

Yellow faceted gemstone, likely citrine or yellow sapphire

Uncertain; probable quartz (SiO₂) or corundum (Al₂O₃)

Tumbled cream-colored pebble

Likely quartz-rich sandstone or limestone; exact identification requires testing

Chert / Flint

Silicon Dioxide (SiO2)

Slate

Metamorphic Pelitic Rock

Slate

Metamorphic Pelitic Rock

Chert (Chalcedony/Agate variety)

Silicon Dioxide (SiO2)

Amber

Fossilized Tree Resin (Succinite)

Nephrite Jade

Nephrite

Blue chalcedony cabochon (likely)

Chalcedony, microcrystalline SiO₂; possibly blue agate or common opal, which cannot be distinguished confidently from the image

Goldstone (blue/black aventurine glass)

Man-made aventurine glass; silica glass containing metallic copper or other glittering inclusions

Yellow Ocher (Limonite)

Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O

Polished blue-green glassy slag or coated mineral fragment

Most likely man-made colored glass/slag; exact composition cannot be determined visually

Diamond

Carbon (C)

Carved labradorite fish

Labradorite, calcium-rich plagioclase feldspar (approximately (Ca,Na)(Al,Si)₄O₈)

Tumbled chert or jasper pebble

Microcrystalline quartz (SiO₂), likely chert/jasper

Flint (gray chert)

Microcrystalline quartz (SiO₂), a variety of chert

Black Obsidian

Volcanic Glass (predominantly SiO2, Silicon Dioxide)

Chert (Honey Chert / Flint)

Silicon Dioxide (SiO2)

Chert

Microcrystalline silica (SiO2)

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Chert (Jasper/Flint)

Silicon Dioxide (SiO2)

Flint / Chert Pebble

Microcrystalline Quartz (SiO2)

Chert (and Agate/Chalcedony)

Microcrystalline Quartz (SiO2)

Chalcedony (likely blue agate) knapped into an arrowhead

Microcrystalline quartz, SiO₂ (chalcedony)

Chert (Flint)

Silicon Dioxide (SiO2)

Polished amethyst-bearing quartz

Quartz, SiO₂; purple coloration from irradiation and trace iron

Yellow faceted gemstone, likely citrine or synthetic glass

Citrine (quartz, SiO₂) is the leading natural possibility; visual identification is uncertain from the photograph

Likely flint (chert) fragment

Chert, microcrystalline quartz (SiO₂)

Jasper / Chert (Red)

Cryptocrystalline quartz (SiO2)

Red coral (likely precious coral)

Corallium sp.; calcium-carbonate skeleton, primarily calcite

Chert (specifically Flint or Nodular Chert)

Silicon dioxide (SiO2)

Chert (Jasper/Flint var.)

Silicon Dioxide (SiO2)

Chert (often called Flint or River Stone)

Microcrystalline alpha-quartz (SiO2)

Chert (Chert / Flint Variety)

Microcrystalline / Cryptocrystalline Quartz (SiO2)

Colorless faceted gemstone, likely glass or cubic zirconia

Uncertain; possible cubic zirconia (ZrO₂) or quartz (SiO₂), but the image may show a man-made simulant

Tiger Shark Fossil Tooth

Galeocerdo cuvier (fossilized)

Asphalt aggregate (crushed stone in bitumen)

Artificial composite; predominantly crushed granite, basalt, limestone, and/or recycled aggregate bound by bitumen

Diamond (as set in a gold ring)

Carbon (C)

Green Slag Glass

Amorphous Silica / Glassy Blast Furnace Slag

Slag (Industrial Byproduct)

Ferro-silicate glass (Slag)

Sea Glass (Uranium/Vaseline Glass variant)

Silicon Dioxide (SiO2) with trace Uranium Oxide (U3O8)