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

Vesicular basalt

Basalt, a mafic volcanic rock composed mainly of plagioclase feldspar, pyroxene, and often olivine

Vesicular basalt (possibly slag-contaminated)

Basalt; chiefly plagioclase and pyroxene, with possible olivine and secondary minerals

Dyed Blue Agate

Chalcedony (SiO2) with artificial dye

Blue goldstone beads

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

Green Banded Agate

Cryptocrystalline microcrystalline Quartz (SiO2)

Green Tiger's Eye

Quartz pseudomorph after crocidolite (SiO2)

Prasiolite

Silicon Dioxide (SiO2) with iron impurities

Likely weathered limestone or calcareous concretion

Calcite-rich carbonate rock; chiefly calcium carbonate (CaCO₃)

Titanium Quartz (Aura Quartz)

Silicon Dioxide (SiO2) treated with Titanium

Dyed Blue Agate Slice

Chalcedony (Silicon Dioxide, SiO2)

Tumbled quartz-rich stone, possibly druzy quartz or chalcedony

Quartz/chalcedony (SiO₂); exact identification is uncertain from the photograph

Concrete or asphalt-like aggregate surface with a dark fragment

Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock

Dyed Agate Slice

Silicon Dioxide (SiO2) with artificial colorants

Dyed Dragon Vein Agate

Silicon Dioxide (SiO2) with artificial dye

Leopard skin jasper (orbicular jasper)

Microcrystalline quartz (SiO₂), commonly with iron-oxide and other silicate inclusions

Tumbled orange chalcedony or jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper

Tumbled polymetallic mineral specimen, likely chalcopyrite-bearing ore

Probable chalcopyrite (CuFeS₂) with quartz and iron-oxide minerals; exact identification is uncertain from the photograph

Conglomeratic aggregate / pebble-rich concrete-like rock

Polymictic conglomerate (likely glacial or beach-derived gravel matrix); exact identification uncertain from image

Blue Goldstone

Goldstone (artificial glass)

Dyed blue howlite or magnesite (tumbled stone)

Howlite: Ca₂B₅SiO₉(OH)₅; commonly sold dyed blue to imitate turquoise

Tumbled chert or jasper pebble

Microcrystalline quartz (SiO₂), commonly called chert; opaque varieties are jasper

Blue Obsidian

Volcanic Glass (Silica, SiO2)

Rounded metallic-looking pebble, likely iron-rich rock or slag

Uncertain; possible limonite/goethite-rich ironstone, hematite-bearing material, or industrial slag

Frosted Quartz

Silicon Dioxide (SiO2)

Blue Obsidian

Volcanic Glass (Amorphous)

Dyed Agate Slice

Microcrystalline Quartz (SiO2) with artificial pigment

Dyed blue tumbled stone, likely howlite or magnesite

Howlite (Ca₂B₅SiO₉(OH)₅) or magnesite (MgCO₃), artificially dyed blue

Dyed Pink Agate Slice

Silicon Dioxide (SiO2) - Chalcedony variety Agate

Dyed Quartz

Silicon Dioxide (SiO2)

Weathered stone, likely sandstone or altered volcanic rock

Indeterminate; possibly quartz-rich sandstone or weathered tuff

Pink Anthracite Coal (dyed)

Anthracite Coal (Artificially Colored)

Blue Howlite (Dyed)

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)

Dyed Agate (Tumbled)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Dalmation Stone (Dyed)

Peralkaline rhyolite

Weathered concrete or cementitious slab (not natural rock)

Artificial calcium-silicate cement composite; likely Portland cement concrete

Painted River Pebble (likely Basalt or Greywacke)

Aphanitic Lithic Clast with Anthropogenic Pigment coating

Fossiliferous limestone

Calcitic limestone, predominantly CaCO₃ (calcite), with possible shell or coral fossils

Dyed Chalcedony (Agate)

Silicon Dioxide (SiO2) with artificial pigment

Dyed Quartz (imitating Emerald/Green Quartz)

Silicon Dioxide (SiO2) with artificial pigment

Orange Quartz (or Citrine Quartz)

Silicon Dioxide (SiO2)

Dyed Agate

SiO2 (Silicon Dioxide)

Tumbled iron-rich stone, possibly jasper or weathered basalt

Indeterminate; likely iron-stained microcrystalline quartz (jasper) or altered basalt