Antropogenic (Man Made Material)

Diamond (as set in a metal alloy ring)

Diamond (Pure Carbon, C)

Dark rounded pebble, likely basalt or slag

Probable fine-grained mafic rock; possibly basalt (plagioclase–pyroxene) or industrial iron/steel slag

Green Aventurine

Quartz (SiO2) with Fuchsite inclusions

Polished jasper pendant

Jasper, microcrystalline quartz (SiO₂) with iron-oxide and other mineral inclusions

Polished orbicular jasper

Jasper, microcrystalline quartz (SiO₂), with iron oxides and other inclusions

Sandstone

Arenite

Diamond (in jewelry setting)

Diamond (C - Carbon)

Rounded pink granite cobble

Granite, chiefly quartz–alkali feldspar–plagioclase–biotite

Blue chalcedony bead necklace

Chalcedony, microcrystalline quartz (SiO₂), commonly blue-dyed or blue-gray natural chalcedony

Coquina

Bioclastic Limestone (Calcium Carbonate, CaCO3)

Chert or silicified sedimentary fragment (tentative)

Microcrystalline quartz (SiO₂), possibly silicified limestone or fossil-bearing chert

Sandstone (likely Fossiliferous)

Arenite / Fossiliferous Sandstone (SiO2 composition)

Chert (Flint)

Chert (Cryptocrystalline Silica, SiO2)

Chert (and associated river cobbles)

Silicon dioxide (SiO2)

Chert (and/or Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (often called Flint)

Chert (SiO2)

Green Slag Glass

Cullet (Amorphous Silicon Dioxide with impurities)

Amber cabochon pendant

Amber (fossilized plant resin), chiefly polymerized diterpenoid resin

Red jasper (likely)

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

Black-and-white agate or onyx bead necklace

Variegated chalcedony (microcrystalline SiO₂), possibly black-and-white banded agate; some black beads may be dyed chalcedony or hematite

Bituminous Coal (with Anthracite or Vitrinite inclusion)

Organic-rich Sedimentary Rock (Carboniferous classification)

Chert (often called Flint or Agate nodule)

Cryptocrystalline Quartz (SiO2)

Chert (Arrowhead Shard)

Microcrystalline silica (SiO2)

Industrial Slag

Anthropogenic Vitreous Slag

Chipped Glass/Plastic Fragment

Silicon dioxide (SiO2) for glass (amorphous) or various polymer compounds for plastic

Blue faceted gemstone ring, likely synthetic sapphire or blue topaz

Uncertain from image; possible corundum (Al₂O₃) or topaz (Al₂SiO₄(F,OH)₂)

Tumbled ruby-in-zoisite (likely)

Ruby-bearing zoisite; zoisite Ca₂Al₃(SiO₄)₃(OH), corundum ruby Al₂O₃

Paving-concrete aggregate with a rounded stone

Polymictic gravel aggregate; the central clast appears to be weathered sandstone or volcanic rock

White cabochon gemstone, likely milky chalcedony or opalite

Chalcedony: microcrystalline quartz, SiO₂; appearance may also indicate synthetic opalite glass

Yellow Chert (Chalcedony)

Microcrystalline Quartz (SiO2)

Jasper

Silicon Dioxide (SiO2)

Coquina / Fossiliferous Limestone

Coquina (composed primarily of Calcium Carbonate / CaCO3)

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

Graphite

Graphite (Carbon, C)

Diamond

Carbon (C)

Polished yellow-green serpentine pendant

Serpentine-group minerals, chiefly antigorite and/or lizardite; approximate formula Mg3Si2O5(OH)4

Chert (Flint)

Microcrystalline quartz (SiO2)

Larimar

Pectolite

Sandstone

Arenite

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Iron Slag

Ferrous slag (primarily silicates and oxides of calcium, iron, and magnesium)