Sedimentary (If Natural Jasper) Or Artificial (If Slag)

Concrete with Aggregate

Artificial Conglomerate (Cement and Aggregate)

Jasper

Silicon dioxide (SiO2)

Blue Dyed Agate Geode

Chalcedony (cryptocrystalline Quartz), SiO2

Yellow Jasper

Jasper (Silicon Dioxide, SiO2)

Dyed Blue Agate

Chalcedony (Silicon Dioxide / SiO2)

Heat-Treated Citrine (Amethyst)

Silicon Dioxide (SiO2) with iron impurities

Dyed Agate

Chalcedony (SiO2)

Iridescent polished/tumbled stone (likely coated quartz or glassy synthetic material)

Indeterminate; possibly quartz (SiO₂) with an artificial iridescent coating

Tumbled jasper (likely brecciated or red jasper)

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

Smoky Quartz

Silicon Dioxide (SiO2)

Probable iron-rich mineral or weathered rock fragment

Indeterminate; possibly limonite/goethite-bearing material

Small dark rock fragment (likely basalt or slag)

Tentatively basalt; exact identification is uncertain from the photograph

Red Jasper (Beach Pebble)

Jasper (Cryptocrystalline Quartz, SiO2)

Blue Slag Glass

Ferro-silicate glass (Slag)

Polished chrysoprase (likely dyed or treated)

Chalcedony, cryptocrystalline quartz (SiO₂), colored green by nickel

Peacock ore (likely chalcopyrite-bornite specimens)

Iridescent chalcopyrite, CuFeS₂, commonly altered to bornite, Cu₅FeS₄

Weathered basalt pebble

Basalt, a mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with olivine and iron-titanium oxides

Likely weathered iron-rich rock or slag fragment

Uncertain; possibly limonite/goethite-rich material (FeO(OH)·nH₂O)

Likely silicon carbide (carborundum)

Synthetic silicon carbide (SiC), likely blue-green crystalline grit

Dark rounded pebble, likely basalt or slag

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

Polished mahogany obsidian

Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)

Bismuth crystal

Bismuth (Bi), artificially crystallized

Tumbled chert or jasper pebble

Microcrystalline quartz (SiO₂), likely chert/jasper

Dyed and polished agate pebble

Microcrystalline quartz (SiO₂), likely chalcedony/agate with blue dye

Blue chalcedony (likely dyed or coated)

Chalcedony, microcrystalline quartz (SiO₂)

Crackled Quartz (Dyed)

Silicon Dioxide (SiO2)

Citrine (Iron-stained Quartz)

Silicon Dioxide (SiO2)

Polished orbicular jasper or rhyolitic jasper

Silica-rich microcrystalline quartz/chalcedony (SiO₂), likely jasper with contrasting mineral veins

Green cabochon gemstone, likely aventurine or dyed chalcedony

Indeterminate from image; possible quartz variety (SiO₂), including aventurine quartz or chalcedony

Jasper

Silicon Dioxide (SiO2) with impurities

Carved smoky quartz (likely)

Quartz, silicon dioxide (SiO₂), smoky variety

Tumbled jasper (likely brecciated or red jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions

Dyed red crystal aggregate, likely quartz or salt

Uncertain; possibly dyed quartz (SiO₂) or halite (NaCl)

Blue Quartzite (Dyed Quartzite)

Quartzite (SiO2 with dye enhancements)

Jasper and Agate

Microcrystalline Quartz (SiO2)

Brecciated Jasper

SiO2 (Silicon Dioxide)

Dyed tumbled stone, likely chalcedony or quartz

Microcrystalline quartz (SiO₂), probably dyed magenta

Tumbled amber-colored mineral or glassy pebble

Uncertain; likely chalcedony/quartz, possibly resinous amber or slag glass

Trilobite Fossil (Flexicalymene)

Flexicalymene ouzregui

Dalmation Stone (Dalmation Jasper)

Peralkaline Rock with Feldspar and Arfvedsonite

Likely tumbled yellow-orange mineral or glassy stone

Indeterminate from photograph; possibilities include yellow jasper, calcite, agate, or dyed quartz

Smoky Quartz

Smoky Quartz (SiO2)